The complaint relates to the broadcaster's editing of a speech he made in 2021 on the day his supporters stormed the Capitol building.
Clips were spliced together from sections of the US president's speech on January 6 2021 to make it appear he told supporters he was going to walk to the US Capitol with them to "fight like hell".
It aired in the documentary Trump: A Second Chance?, which was broadcast by the BBC the week before last year's US election.
The US president is seeking damages of no less than $5bn (£3.7bn) under a defamation lawsuit.
He has also sued for $5bn for alleged violation of a trade practices law.
Both lawsuits have been filed in Florida.
'They put words in my mouth'
Speaking in the Oval Office earlier on Monday, he said: "In a little while, you'll be seeing I'm suing the BBC for putting words in my mouth.
"Literally, they put words in my mouth. They had me saying things that I never said coming out."
The scandal erupted earlier this year after a leaked memo highlighted concerns over the way the clips were edited.
Responding to the lawsuit, a BBC spokesperson said: "As we have made clear previously, we will be defending this case. We are not going to make further comment on ongoing legal proceedings."
After the leak, BBC chair Samir Shah apologised on behalf of the broadcaster over an "error of judgement" and accepted the editing of the 2024 documentary gave "the impression of a direct call for violent action".
The fallout from the saga led to the resignation of both the BBC director-general Tim Davie and the head of news Deborah Turness.
Earlier, BBC News reported the broadcaster had set out five main arguments in a letter to Mr Trump's legal team as to why it did not believe there was a basis for a defamation claim.
In November, the BBC officially apologised to the president, adding that it was an "error of judgement" and saying the programme will "not be broadcast again in this form on any BBC platforms".
A spokesperson said "the BBC sincerely regrets the manner in which the video clip was edited", but they also added that "we strongly disagree there is a basis for a defamation claim".
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Speaking on Mornings with Ridge and Frost, health minister Stephen Kinnock backed the BBC.
He said: "Well, it's absolutely right that the BBC is an independent organisation.
"I think they have apologised for one or two of the mistakes that were made in that Panorama programme. But they've also been very clear that there is no case to answer in terms of Mr Trump's accusations on the broader point about, libel or defamation. So, you know, I think it's right that the BBC stands firm on that point.
"Yes, there were some mistakes made in that particular piece of film, but I think the broader argument that they were making, they're right to stick by their guns on that. And I hope that they will continue to do so as an independent organisation, of course, funded by the licence fee, a hugely important institution."
He added: "I am a massive supporter. The government is a massive supporter of the BBC. The Labour Party will always stand up for the BBC as a vitally important institution, in both our political life and of course, in terms of entertaining and informing the British public."
Liberal Democrat leader Sir Ed Davey said: "Keir Starmer needs to stand up for the BBC against Trump's outrageous legal threat and protect licence fee-payers from being hit in the pocket.
"The Trump administration has clearly set out they want to interfere in our democracy, which includes undermining our national broadcaster.
"The prime minister needs to make clear this is unacceptable."
In an extraordinarily blunt intervention, Air Chief Marshal Sir Richard Knighton warned that Russia's military strength is increasing and is something to fear, with Russian troops now battle-hardened after spending the past nearly four years waging a full-scale war in Ukraine.
He said the UK's armed forces would always be the first line of defence alongside the rest of the NATO alliance, but the whole of society must also play a part in rebuilding resilience.
The chief of the defence staff said it is important to be honest with "families and households" across the UK about what it means to be prepared for "an array of real, physical threats".
UK's 'sons and daughters' must be ready
Serving up a sombre reality check, Air Chief Marshal Knighton said he agreed with his French counterpart, General Fabien Mandon, who said last month that France must be ready for the possibility of losing its children in a potential war with Russia.
"The situation is more dangerous than I have known during my career, and the price of peace is rising," the British defence chief said.
"Our response needs to go beyond simply strengthening our armed forces. It needs a whole of nation response that builds our defence industrial capacity, grows the skills we need, harnesses the power of the institutions we will need in wartime and ensures and increases the resilience of society and the infrastructure that supports it."
He continued: "Sons and daughters. Colleagues. Veterans. …will all have a role to play.
"To build. To serve. And if necessary, to fight. And more families will know what sacrifice for our nation means."
Most people in the UK, though, no longer have direct experience of the armed forces thanks to the peace that followed the end of the Cold War almost 35 years ago.
The military chief noted that it was 65 years ago this month since the last national service call-ups took place, and 80 years since the end of the Second World War.
But he indicated that the kind of national defence and resilience that was once second nature to UK society up until the collapse of the Soviet Union needs to return.
He said that while there was only deemed by defence analysts to be a "remote" chance of up to a 5% of Russia launching a "significant direct attack or invasion" against the UK, this "does not mean the chances are zero".
Russian threat 'worsening'
Air Chief Marshal Knighton said: "My point is that none of us can say with any certainty what the absolute risk might be. And even though simple binary statements might be easy for people to engage with, they risk instilling panic or complacency.
"What really matters is the trend. Are the chances of conflict growing?
"And here, I think the evidence is clear that the trend, from Russia in particular, is worsening, and that is the key argument for action."
Turning to the capability of the Russian armed forces, despite being locked in a major war against Ukraine, he said their "hard power is growing quickly".
"Over the past 20 years, Russia has delivered significant defence reform and investment into what were weak and hollowed-out armed forces," he added.
"The Russian armed forces are now more than 1.1 million strong, consuming more than seven per cent of GDP, and around 40% of government spending, which is a sum that has more than doubled over the past decade."
By contrast, the UK army is a little over 70,000 soldiers, with the government only committed to increasing defence spending to 2.5% of GDP from 2.3% by 2027.
Russian power 'something to fear'
"We should be under no illusions that Russia has a massive, increasingly technically sophisticated, and now, highly combat-experienced, military," the military chief said.
He described how Russia is "developing new and destabilising weapons systems such as nuclear-armed torpedoes and nuclear-powered cruise missiles putting nuclear weapons in space. So it is absolutely clear that Russia's hard power is something to fear, but what about Russia's intent to use it?"
The military chief said the war in Ukraine and Russia's willingness to target its neighbouring states show it "wishes to challenge, limit, divide and ultimately destroy NATO".
But he acknowledged this threat is not yet felt in the UK as it is in countries that share physical land borders with Russia.
In a sign that he is seeking a more rapid increase in defence spending, he said Germany expects to spend 3.5% of GDP on defence by 2029, while Poland is already at 4.2%.
"And we have seen just in the past few weeks France and Germany return to a form of national service."
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He continued: "In reality, other than proximity, the threat in the UK isn't really any different to the threat in Germany, for example.
"Unless we are able to raise awareness and stimulate the conversation with society about the risks, we can't expect the rest of government, society, and industry to act or bear the costs."
The defence chief called out a podcast series by Sky News and Tortoise called The Wargame, which simulates a Russian attack on the UK, as an example of efforts in the media to raise public awareness.
Building on the success of the highly acclaimed podcast The Wargame, Sky News presents The Wargame: Decoded - a one-off live event that takes you deep inside the minds of the wargame's participants. Discover how they tackled the toughest challenges, the decisions they made under intense pressure, and even experience key moments of the game for yourself.
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Sky News' Deborah Haynes will guide the conversation with Sir Ben Wallace, Robert Johnson, Jack Straw, Amber Rudd, Keir Giles and General Sir Richard Barrons - real-life military chiefs, former government officials and leading experts. Together, they will unpack their experiences inside The Wargame, revealing the uncertainty, moral dilemmas and real-world pressures faced by those who must make decisions when the nation is under threat.
Join us for this unique event exploring how the UK might respond in a moment of national crisis and get a rare, unfiltered glimpse into how prepared the country truly is for war.
A hydrangea is thriving in a shady spot and the borders are still in bloom. The man inside can give his neighbours advice on everything from ericaceous compost and fertiliser but he can't earn a living from it.
Mick is a landscape gardener by trade but has been unemployed for almost a decade now because of his health, which deteriorated rapidly after a heart attack in his 30s.
A few years later, an operation to remove a clot in his right leg resulted in an amputation.
In 2016, he also lost his left leg to vascular disease. Now in his 60s, he still wants to work but the opportunities available to him are slim.
Still, he counts himself lucky. "I know I'm getting on a bit now. I've lost my legs, but I can still do certain amounts of stuff.
"There are people out there who struggle to get out of bed in the morning, but they're having their benefits cut because they're saying they are fit for work. It's ridiculous."
It comes as the unemployment rate ticked up to 5.1% in October, from 5% in September.
Statistics met with 'surprise and disbelief'
Mick is among the 10.4 million people of working age who report a disability in Britain today - that's around a quarter of all 16-64 year olds.
It is a statistic that has been met with both surprise and disbelief as policymakers grapple for explanations behind the nation's declining health, which is apparently so bad that 2.8 million people have dropped out of the labour market altogether, meaning they have stopped looking for work.
In Westminster, alarm has slowly crept in as the government struggles to digest the bill: Disabled people are entitled to benefits that support them with the costs of their disability.
They are also less likely to be in work than the rest of the population. The natural consequence is that Britain's benefits bill has ballooned.
One-in-10 people now claim either incapacity or disability benefits. At £76.8bn, about 6% of everything the government spends now goes on these benefits and the costs are only forecast to rise.
Mental ill health
So what is actually going on?
There are no clear-cut answers but a few theories have been put forward: Some say the pandemic has had a clear long-term impact on our health, particularly our mental health.
The workforce is also getting older, so more of us are living with chronic conditions. Then there's the cost of living crisis, which might have pushed more people to claim benefits when they may not have needed to in the past.
In the absence of any concrete explanations, however, the data has also fostered suspicions. Some people believe the system is too soft and that "everyday woes" are being medicalised.
Those "everyday woes" are mental health conditions, like depression and anxiety, which are driving the increase in reported disability.
The vast majority- 86% - of people on health-related benefits now have a mental health condition, even if it is not their primary condition.
After a failed attempt to reform disability benefits, the government has ordered a review into the diagnosis of mental health conditions, as well as autism and attention-deficit hyperactivity disorder (ADHD).
The health secretary has spoken about "overdiagnosis".
Meanwhile, Conservative leader Kemi Badenoch has proposed a "crackdown on people exploiting the system", including those with "mild" conditions like anxiety or depression.
But on the streets of Bidston, where NHS figures suggest 27.7% of people experience depression (more than double the national average), and where almost 40% of working-age people aren't even looking for work, these debates seem to skip over the nuances and, in turn, miss the point.
A combination of ailments
For someone like Mick, who is so physically disabled that no one can accuse him of making it up, it isn't his wheelchair that stops him from looking for work but his periodic bouts of depression. The mental anguish - when it hits - is far more disabling than his physical condition. He would know because he experiences both.
"Oh, God. If it wasn't for my dog, I'll guarantee you, I probably wouldn't be here now because I was in such a dark place," he said.
"So many things were going on in my life at the time, and I was constantly in major pain, but I couldn't get rid of it, no matter what medication I took or anything.
"I wasn't coming out of my house, I didn't open my blinds, I didn't do hardly anything at all, and that's not me."
"Mental health problems have gone through the roof recently," he said. "A lot of people are struggling mentally. I mean, I've gone through it myself."
The trouble with trying to determine "how sick is too sick?" or "how disabled is too disabled?" is that most people report more than one condition, sometimes a mixture of mental and physical conditions.
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For those on incapacity benefits, which are given to people deemed unfit to work, the average is about 2.7 conditions per person.
It could be a bad back that flares up with depression. Or, hearing loss that triggers anxiety.
Eventually, one might take over the other as the primary condition.
Then there are the agonies of life - perhaps a divorce during the cost-of-living crisis that caused emotional despair.
The medical perspective and the cost of living
Dr Mark Fraser, a local GP at the Fender Way Medical Centre, has seen it all.
"Demand has gone up considerably. An awful big driver of that probably is mental health, but we're also seeing a general deterioration in people's health and well-being," he said.
"So, more chronic disease, certainly more cancers, more people are coming to us with lifestyle-related problems."
Across the country, spending on health-related benefits accelerated significantly from 2022, when energy bills started to soar and inflation climbed above 11%.
Dr Fraser is seeing more patients than he used to and almost all of them - from pensioners to young people - are in debt.
"It's more expensive just to stay alive now. The cost of food, the cost of energy, the cost of housing, the cost of clothes, have gone up considerably in price over the last five or 10 years," he said.
"And if you're down at the lower end of income, the impact on that is massively disproportionate. Where the bread line used to be. We're down to the breadcrumbs line.
"There's no doubt that it's very difficult for you to contemplate healthy living when you're awake all night worrying about if you can afford the next bill or if you can afford the next shop."
Increasingly anxious children
The degradation in young people's mental health has been striking, with local GPs increasingly prescribing antidepressants to young people.
At the Fender Way Medical Centre, doctors are increasingly dealing with anxious children and young adults, some of whom are struggling to function and hold down jobs even when they get them.
Dr Fraser said children might be growing up less resilient but they also appear to have been deeply affected by lockdowns, the loss of routine and the closure of local clubs and leisure centres.
"They don't see a bright future for themselves. So they are a little bit resigned... there is despair later," he said.
That despair is also finding its way into his surgery.
"There are more people in acute mental health crises, more often.
"I think that that used to be kind of unusual in general practice for you to be dealing with someone who you were worried wasn't going to make it through the night if you let them go... a person at the point of ending their life... deciding that there is no point in carrying on, what's the point?.. And it's more frequent than it ever used to be."
A nationwide issue
This is likely to ring true for GPs across the country.
Across the country, the number of people in contact with NHS mental health services has risen, as has antidepressant use.
Then there are deaths caused by alcohol, drugs or suicide, which have increased substantially among the working-age population since the pandemic.
They were up 24% - 3,700 deaths - in 2023 compared with pre-pandemic levels in England and Wales.
'Deaths of despair'
It's a phenomenon more closely associated with the US, where deaths linked to opioid use among middle-aged Americans - largely those without college degrees - led economists to first coin the phrase "deaths of despair" about a decade ago.
In Britain, we don't have the same issues but among 45 to 54-year-olds, these deaths are now a bigger killer than heart disease.
So, while greater levels of reporting and diagnosis might be playing a part in the explosion of reported mental health conditions, there is clear evidence that our mental well-being has deteriorated over the past few years in very real ways.
The actual health conditions only tell one part of the story.
The austerity impact
Economic decline, wage stagnation and loss of community might tell another.
Changes to our benefit system, going back decades, could also be playing a part.
During the austerity years, the country's safety net was pared back, with the government cutting housing benefits, raising the state pension age for women and lowering the benefit cap.
But they may have been a false economy. New research by the Institute of Fiscal Studies suggests that they nudged more people onto health-related benefits instead.
David Finch, assistant director at the Health Foundation, which funded the study, said: "Cuts to one part of the welfare system can push people to claim health-related benefits, potentially driven by the cuts worsening health.
"This creates a long-term risk that they spend longer out of the workforce and with lower incomes. Future welfare reform must learn the lessons of the past."
Those lessons are not always immediately obvious but policymakers will have to reach into all corners of society to find them.
Resolving Britain's problem with worklessness will take more than just a carrot or a stick.
Nick Reiner joined his father and mother, Michele Singer Reiner, at the event on Saturday - and the couple were upset and embarrassed about his behaviour, Sky News's US partner NBC News cited a source as saying.
They also expressed concerns about his health.
The outlet cited another source saying Nick's behaviour had made other guests uncomfortable.
They said he interrupted a conversation filmmaker Bill Hader was having with two guests and - when informed it was a private conversation - stood still and stared before storming off.
Reiner and his wife apparently died of stab wounds, US media reported.
The Los Angeles Fire Department initially said a 78-year-old man and a 68-year-old woman were found dead inside a property in the Brentwood neighbourhood, without identifying the victims
The case against Nick Reiner, 32, will be presented to the Los Angeles County district attorney's office for consideration on Tuesday, according to the city's police department.
Police chief Jim McDonnell said the robbery and homicide division was handling the investigation.
"They worked throughout the night on this case and were able to take into custody Nick Reiner, a suspect in this case," he said, calling the deaths "a very tragic incident".
Trump branded 'sick' for response to killings
Meanwhile, Donald Trump has been branded "sick" after launching an extraordinary attack against the senior Reiner, describing him on Truth Social as "tortured and struggling, but once very talented".
Mr Trump said Reiner and his wife died "reportedly due to the anger he caused others through his massive, unyielding, and incurable affliction with a mind crippling disease known as TRUMP DERANGEMENT SYNDROME, sometimes referred to as TDS".
"He was known to have driven people CRAZY by his raging obsession of President Donald J. Trump, with his obvious paranoia reaching new heights as the Trump Administration surpassed all goals and expectations of greatness, and with the Golden Age of America upon us, perhaps like never before. May Rob and Michele rest in peace," he wrote.
Celebrities and politicians have criticised Mr Trump for his comments, labelling them "disgusting" and "petty".
'Can you get any lower?'
"What a disgusting and vile statement," actor Patrick Schwarzenegger said on X, while Californian Democrat Zoe Lofgren condemned Mr Trump's comments as "a new low for this petty, hateful man".
Talk show host Whoopi Goldberg compared the president's comments to those he made after the assassination of right-wing activist Charlie Kirk, when Mr Trump hit out at critics.
"I don't understand the man in the White House. He spoke at length about Charlie Kirk and about caring, and then this is what he puts out. Have you no shame? No shame at all? Can you get any lower? I don't think so," she said.
'Sick'
"This is a sick man," California governor Gavin Newsom wrote on X.
Republican US House member Thomas Massie also addressed the comments, saying: "Regardless of how you felt about Rob Reiner, this is inappropriate and disrespectful discourse about a man who was just brutally murdered."
Who are the Reiners?
Nick Reiner has spoken publicly of his struggles with addiction. He cycled in and out of treatment facilities by the age of 18, with periods of homelessness and relapses in between.
He and his father explored their difficult relationship and his struggles with heroin addiction and homelessness in a 2016 film called Being Charlie, which they co-wrote.
Republican congresswoman Marjorie Taylor Greene referred to Nick Reiner's "drug addiction and other issues" in a statement on X.
"This is a family tragedy, not about politics or political enemies," Ms Taylor Greene said. "Many families deal with a family member with drug addiction and mental health issues. It's incredibly difficult and should be met with empathy especially when it ends in murder."
Rob Reiner was a celebrated director whose work included some of the most memorable movies of the 1980s and 1990s.
He directed classics such as This Is Spinal Tap, The Princess Bride, When Harry Met Sally, A Few Good Men and Stand By Me.
He also acted, starring in Sleepless In Seattle and The Wolf Of Wall Street among others. His most recent high-profile work was a recurring guest role in the hit show The Bear.
He met Michele Singer in 1989, while directing When Harry Met Sally. They have three children together.
Singer used to work as a photographer and took the photo of Donald Trump that appears on the cover of his book Trump: The Art Of The Deal.
'The stuff of Greek tragedy'
Former US president Barack Obama has led tributes. He wrote on X that "Michelle and I are heartbroken by the tragic passing of Rob Reiner and his beloved wife, Michele. Rob's achievements in film and television gave us some of our most cherished stories on screen".
Harry Shearer, who collaborated with Reiner on This Is Spinal Tap, said in a statement: "Rob was a friend and collaborator through much of my life. He was funny, he was smart, he was a mensch."
He said Reiner's wife was a "very good friend" to his own wife, Judith, adding: "This is unspeakable, the stuff of Greek tragedy."
Christopher Guest, who starred in Reiner's films This Is Spinal Tap and The Princess Bride, and his wife Jamie Lee Curtis said in a joint statement that they were "numb and sad and shocked about the violent, tragic deaths of our dear friends Rob and Michelle Singer Reiner".
Read more: Reiner spoke to Eric Idle about future before death
Reiner was a champion of liberal causes and a political activist.
In the 2004 presidential election, he backed Democrat candidate John Kerry and featured in advertisements taking aim at incumbent president George W Bush.
Reiner also supported Democratic presidential hopefuls Al Gore and Hillary Clinton.
"This is a devastating loss for our city and our country. Rob Reiner's contributions reverberate throughout American culture and society, and he has improved countless lives through his creative work and advocacy fighting for social and economic justice," Los Angeles mayor Karen Bass said.
California governor Mr Newsom paid tribute to Reiner's activism as he said he was "heartbroken" over the director's death.
The treat typically contains a filling made of pistachio, tahini, and shredded filo pastry, and has soared in popularity over the past year.
But the Food Standards Agency (FSA) said it had found "several" of these products in the UK which failed to meet safety and labelling requirements.
Rebecca Sudworth, FSA director of policy, said: "We've found that some products contain peanut and sesame that aren't declared on the label."
It would therefore be "dangerous" for consumers with allergies to buy the bars, the organisation said.
The watchdog says it is currently reviewing sampling data from products on sale to check whether they meet food safety standards.
But until its full results are known, the body is advising consumers with allergies to avoid Dubai-style chocolate as a precaution.
Ms Sudworth added: "People with an allergy should not eat Dubai-style chocolate.
"If you're buying a gift for someone who lives with allergies, our advice is to avoid buying these products. This includes all allergies, not just peanut and sesame.
"People without allergies can consume these products, especially where they are supplied by reputable brands and retailers."
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Jessica Merryfield, head of policy and campaigns at the Chartered Trading Standards Institute (CTSI), warned that failing to comply with food labelling rules was "highly dangerous".
She said: "The legal requirements on this are clear - any food containing allergens needs to be clearly identified and labelled as such to allow consumers to make informed and safe choices.
"To not do this is illegal and also highly dangerous as it makes such foods unsafe to those with food allergies.
"We urge all food businesses, including retailers and importers, to take immediate steps to comply."