At stake are huge consequences not just for Ukrainians, but for Europe and the wider international order - whether borders can be changed by force.
On the ground, the conflict feels less like grand strategy and more like a daily slog to survive.
We joined a unit from the 117th Brigade, tasked with defending one of the most heavily contested areas of the Donbas, known as the "fortress belt".
Just getting to their positions is a test of nerve, as moving forward often means walking across open ground. It is terrifying.
All around, the landscape bears the scars of war. It used to be only the scream of a shell you had to fear, but now it is also the menacing buzz of a drone - and the sky here is full of them.
A drone spots us
The soldiers scan the skies for any unmanned aerial vehicles (UAVs) and use handheld drone detectors.
One drone heads over our position, hunting for a target, and the radio soon alerts us that it is tracking back. The drone detector doesn't stop bleeping, indicating that our movement has been spotted.
We hear it before we see it, and the increasingly louder whizzing sound means the drone is getting closer and closer.
The deputy commander we are with opens fire with his assault rifle, and another soldier joins the fight. While hitting a small, fast-moving target is not easy, it's the only way to combat the threat and has become routine for the soldiers.
We are relieved when we see the drone fall from the sky, but there is no time to linger, as more drones could follow and artillery might be called in on our position.
The next leg of the journey to the village where the unit is stationed is by quad bike, racing over icy roads.
As we speed forward, smashed Ukrainian vehicles lie abandoned along the route; they are stark reminders of the danger ahead.
Ukrainian drones are our eyes in the sky, tracking our movement overhead, thereby offering some protection.
Cheap, mass-produced and deadly
The small "drone hunter" unit operates largely in the shadows, helping protect the logistical hub of Sloviansk, a key city anchoring the defensive line in eastern Ukraine.
Inside their bunker, where they live and plan missions, they show us a drone they shot down that morning. It is cheap, mass-produced and deadly.
Bohdan, the commander of the anti-aircraft battery unit of the 117th Brigade, explains: "There are men working with pump-action shotguns because the drones fly at their lowest altitude there.
"That is within the effective range for a shotgun. But here, they fly higher and faster so the Kalashnikov is the most effective tool."
Desperate fight for survival
The drones are relentless, and the landscape has been battered by years of war.
The soldiers show us something extraordinary: two civilians are still living in this shattered place.
For four years, Alexander and his wife have survived under constant bombardment. He tells me they are frightened, but have no money and nowhere to go.
As we speak, we move for cover, as another drone has been spotted overhead.
For the men defending this territory, the danger is constant.
One soldier describes the rhythm of their days: "It happens two, three times a day: icy roads, sleeper drones, flying drones, and the Russians. It couldn't be more dangerous. Threats from everywhere - within seconds."
Life in eastern Ukraine is a desperate fight for survival.
Secret underground bunker
We are taken to a secret location deep in a forest. Access to the brigade's headquarters is tightly restricted.
Inside, we descend into a bunker - a labyrinth of screens and monitors that reflects what this war has become.
This is now a conflict of microchips and mud, with drones sketching digital kill chains and men doing whatever they must to survive.
Colonel Dmytro Yaroshenk, the commander of the 117th Brigade, says the transformation has been profound: "The war has changed fundamentally.
"We used to fight 'on horseback', so to speak; now we fight in the sky. We're even taking down helicopters with drones. Not my brigade specifically, but there are units doing it."
On one screen, he shows us what remains of a group of Russian soldiers who tried to use the mist to launch a probing attack. Surveillance drones - and the algorithms guiding them - see everything and everyone.
"Logistics are currently a nightmare because technology has evolved so much; drones are flying almost everywhere. If the enemy spots a vehicle, it's highly likely to be quickly destroyed," the colonel adds.
Another image appears: a bunker where Russian troops were spotted entering. Attack drones are called in, striking the hideout. No one comes out.
The 21st century has fused with the muddied trench battlefields of the First World War, and the result is grim and brutal.
The fighting here may feel remote to those thousands of miles away, but the implications are not.
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This war will help determine whether might makes right in the 21st century, whether international law is enforced or eroded.
After four years of merciless combat, the battle for the Donbas is about more than territory. It is about the kind of world that will emerge when the guns finally fall silent.
The leader of the Jalisco New Generation Cartel, whose real name is Nemesio Ruben Oseguera Cervantes, was wounded in an operation to capture him in Tapalpa, Jalisco state, on Sunday.
He later died while being flown to Mexico City, the country's defence department said.
Jalisco is the base of the cartel known for trafficking large quantities of fentanyl and other drugs to the US.
The cartel was designated as a foreign terrorist organisation by Donald Trump's administration earlier this month.
During the operation, the defence department said troops came under fire and killed four people.
Three others, including Oseguera Cervantes, were wounded and later died.
Two more people were arrested, and armoured vehicles, rocket launchers and other firearms were seized.
Three members of the armed forces were also wounded.
The Foreign Office urged Britons in Mexico to stay indoors and avoid unnecessary travel amid the surge of violence and what it described as "serious security incidents" following "a federal law-enforcement operation against organised crime".
A spokesman said: "You should exercise extreme caution, follow local authorities' advice, including orders to stay indoors and avoid non-essential travel in affected areas."
The US Embassy in Mexico said on X that Mexican special forces carried out the operation "within the framework of bilateral cooperation, with U.S. authorities providing complementary intelligence".
US deputy secretary of state Christopher Landau, previously ambassador to Mexico, said Oseguera Cervantes' killing was a "great development" for the US and Mexico, as well as the rest of Latin America.
The White House press secretary, Karoline Leavitt, confirmed US government involvement in providing intelligence support, accusing Oseguera Cervantes of being "one of the top traffickers of fentanyl".
Roads blocked and cars set on fire
After news of Oseguera Cervantes' death, cartel henchmen blockaded highways with burning cars and torched businesses in several states, paralysing parts of the country.
Such tactics are commonly used by the cartels to block military operations.
In Jalisco's popular beach resort of Puerto Vallarta, frightened tourists on social media described a "war zone" as plumes of smoke billowed into the sky.
Air Canada, United Airlines, Aeromexico and American Airlines suspended flight operations on Sunday.
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The US State Department warned US citizens in Jalisco, Tamaulipas, Michoacan, Guerrero and Nuevo Leon states to remain in safe places while security operations are carried out.
Jalisco governor Pablo Lemus told residents to stay at home and suspended public transportation. Schools in the state have also been closed on Monday.
Reaction to operation
In a post on X, President Claudia Sheinbaum said: "There is full coordination with the governments of all states; we must remain informed and calm... in most parts of the country, activities are proceeding normally.
"My recognition goes to the Mexican Army, the National Guard, the Armed Forces, and the Security Cabinet. We work every day for the peace, security, justice, and well-being of Mexico."
She said she would strengthen efforts to cooperate with the US to fight cartels, but vowed to uphold Mexico's sovereignty and warned against any unilateral military action by the US in Mexico.
In January, after the US capture of Venezuelan President Nicolas Maduro, Mr Trump said "the cartels are running Mexico", and warned "we are going to start now hitting land with regard to the cartels".
The US State Department had offered a reward of up to $15m for information leading to the arrest of El Mencho.
Oseguera Cervantes was heavily involved in drug trafficking since the 1990s.
He was convicted of conspiracy to distribute heroin in the US District Court for the Northern District of California in 1994 and spent almost three years in prison.
Following his release from custody, Oseguera Cervantes returned to Mexico and continued drug trafficking operations.
Since 2017, he has been indicted several times in the United States District Court for the District of Columbia.
One of Mexico's most powerful criminal organisations
The Jalisco New Generation Cartel is one of the most powerful and fastest-growing criminal organisations in Mexico.
The cartel carried out a daring assassination attempt in 2020 with grenades and high-powered rifles against the then-head of the capital's police force, who is now head of federal security, in the heart of Mexico City.
The US Drug Enforcement Administration considers it to be as powerful as the Sinaloa cartel, one of Mexico's most notorious criminal groups.
The cartel has a presence in all 50 US states and is believed to be one of the leading suppliers of cocaine to the US market.
Like the Sinaloa cartel, it earns billions of dollars from the production of methamphetamines and fentanyl.
The man was seen by the north gate of the Florida property at around 1.30am local time (6.30am UK time) on Sunday. He was carrying what appeared to be a shotgun and a fuel can, officials added.
US media have identified the suspect as Austin Tucker Martin - a 21-year-old who was reported missing by his family a few days ago.
Rick Bradshaw, the sheriff of Palm Beach County, said the man made it into Mar-a-Lago's inner perimeter. He is believed to have driven through the north gate of the estate as another vehicle was exiting.
The man raised his shotgun to a shooting position after being confronted by a deputy and two Secret Service agents, who then "fired their weapons and neutralised the threat", the sheriff added.
Secret Service spokesman Anthony Guglielmi said the suspect was in his early 20s and from North Carolina.
According to Mr Guglielmi, investigators believe he left North Carolina and headed south, picking up a shotgun along the way. The box for the gun was recovered in his vehicle.
Investigators are working to compile a psychological profile while the motive is still under investigation.
Suspect 'from family of Trump supporters', says relative
The suspect's cousin, Braeden Fields, 19, spoke with a reporter from the Associated Press, stating: "We are big Trump supporters, all of us. Everybody."
But he said his relative didn't discuss politics and was "real quiet, never really talked about anything".
"He's a good kid," Mr Fields said, adding that Martin sent part of every pay cheque from his job at a local golf course to charity.
"I wouldn't believe he would do something like this. It's mind-blowing."
While Mr Trump often spends the weekends at Mar-a-Lago, he was at the White House with his wife Melania when the incident took place.
White House praises Secret Service
White House press secretary Karoline Leavitt said the Secret Service had acted "quickly and decisively to neutralise a crazy person" who had intruded into Mr Trump's home.
She wrote on X: "Federal law enforcement are working 24/7 to keep our country safe and protect all Americans. It's shameful and reckless that Democrats have chosen to shut down their Department."
Earlier this month, Democrats in the US Senate blocked a funding package for the Department of Homeland Security, which includes the Secret Service, over their opposition to an immigration crackdown that has triggered widespread protests and seen two people killed in Minneapolis.
The FBI has asked residents who live near Mar-a-Lago to check any security cameras as they may have footage that could help investigators.
Five days ago, US Capitol Police arrested a Georgia gunman armed with a shotgun as he sprinted towards the west side of the Capitol.
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Mr Trump previously faced a threat to his life when he was wounded during an assassination attempt during a campaign rally in Butler, Pennsylvania, on 13 July 2024.
On 15 September 2024, a man with a rifle was captured after waiting near Mr Trump's golf course in West Palm Beach while the president played a round. He was sentenced to life in prison earlier this month.
Aramayo won the award for his performance in I Swear, which tells the real-life story of Tourette's campaigner John Davidson, while Irish actress Jessie Buckley was named best actress for her performance in the Shakespeare biopic Hamnet.
Paul Thomas Anderson's comedy-thriller One Battle After Another, starring DiCaprio, Teyana Taylor, Chase Infiniti and Sean Penn, was the biggest winner of the night, picking up six BAFTAs including best film, best director, and supporting actor for Penn.
Accepting the best film award, Anderson - who had earlier almost dropped his BAFTA for best adapted screenplay - said it was a "tremendous honour", adding: "Anybody who says that movies aren't good any more can piss right off because this is a great f***ing year."
Prince William, who is president of BAFTA, and Kate were in the room to cheer the winners on, alongside other stars including nominees Emma Stone and Kate Hudson, music stars Little Simz, Stormzy and Jessie Ware, and Kylie Jenner - here in the UK to support her boyfriend Chalamet.
Snacks for the stars
Host Alan Cumming brought some humour to the show, offering snacks to the A-listers - Jammie Dodgers for Chalamet and Jenner, Twiglets for Rose Byrne, and an oaty flapjack for DiCaprio (who said it sounded "fantastic").
During his speech, Aramayo was cheered on by his dad, and became emotional as he told the BAFTAs audience: "I honestly cannot believe that I have won this award."
The 33-year-old, who grew up in Hull, thanked fellow nominee Ethan Hawke, and said: "Everyone in this category blows me away.
"When I was in school, Ethan Hawke came in to speak to us in Julliard and he gave an amazing talk on longevity as an actor, about protecting your instrument and avoiding self-destructive behaviours, and it had a great impact on everyone in the room.
"So to be in this category with you tonight is incredible. Thank you, Ethan."
The award was his second of the night, coming not long after he had accepted the rising star prize - the only one to be chosen by a public vote - and I Swear also picked up a third award for its casting.
'Nuclear bad fake tan'
In contrast to Aramayo, Buckley was the favourite to win the best actress award after picking up the prize at the Critics Choice Awards and Golden Globes earlier this year. She is the first Irish star to take home the prize.
"As a little girl, I never in a million years thought I would get to make a film," she said in her speech.
Recalling her early days as an actress, she said: "I had nuclear bad fake tan on, white hoop earrings, a polka-dot red skirt and had the audacity to say one day I wanted to be like Judi Dench."
Buckley, who rose to fame on the talent show I'd Do Anything, coming runner-up in the series' search to find a lead to play Nancy in the 2009 West End revival of the British musical Oliver, said it was "nuts" to be on stage, winning a BAFTA, and paid tribute to the "women past, present and future who taught me and continue to teach me how to do it differently".
Addressing her fellow nominees, the Irish actress said: "You are all just radical and you are doing it for the naughty girls, and I'm in awe of all your incredible performances."
She also dedicated the award to her daughter, saying: "It's the best role of my life being your mum and I promise to continue to be disobedient so you can belong to a world in all your complete wildness as a young woman. I am very grateful for this."
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Wins for Sinners and Frankenstein
Paul Mescal plays Shakespeare alongside Buckley, who plays his wife, Agnes, in Hamnet. The film tells the story of the death of their son, Hamnet, from the plague, and how Shakespeare was inspired to write Hamlet.
Buckley's win was one of two for the film, which also picked up the prize for outstanding British film.
Producer Sir Sam Mendes acknowledged the other nominees in the category and said: "We are not great as an industry or a culture for patting ourselves on the back, but perhaps we should."
Elsewhere, period vampire horror Sinners, starring Michael B Jordan, picked up three awards, including best supporting actress for British star Wunmi Mosaku, and the prizes for original screenplay and score. Frankenstein, starring Jacob Elordi, also won three - for costume, make-up and hair, and production design.
Targeted interventions such as small-group language work will receive funding, and there will be help for staff to introduce adaptive teaching styles, as part of a major government overhaul to be announced on Monday.
Some £1.6bn over three years will be provided to early years, schools and colleges through an "inclusive mainstream fund".
Another £1.8bn over the same period will go towards creating an "experts at hand" service, made up of specialists such as SEND teachers and speech and language therapists in every area.
Schools will be able to draw from this bank on demand regardless of whether pupils have education, health and care plans (EHCPs) - legal documents setting out the support children with SEND are entitled to - the Department for Education (DfE) said.
A further £200m will be invested in SEND outreach teams for communities, and another £200m for local authorities to "transform how they operate in line with our reforms while maintaining current SEND services", the DfE said.
Unions broadly welcomed the commitment to reform but warned they would be scrutinising the detail when the Schools White Paper is released to see whether the changes are enough.
Prime Minister Sir Keir Starmer promised "tailored support" for families and an end to the "one size fits all system".
"I've heard first hand the struggles and exhaustion faced by too many parents who feel they have to fight the system to get their child the support they need," he said.
"But getting the right support should never be a battle - it should be a given."
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Education Secretary Bridget Phillipson said the government was "fiercely ambitious for children and young people with SEND", who deserve a system that "lifts them up, and that puts no limit on what they can go on to achieve".
She said: "These reforms are a watershed moment for a generation of young people and generations to come, and a major milestone in this government's mission to make sure opportunity is for each and every child."
But public service union Unison said the money "has to go where it's needed" and "exactly how that will happen under these new plans is not clear".
Head of education at the union Mike Short said: "The broad themes in the White Paper are encouraging and cutting the disadvantage gap is key if every child is to achieve and thrive.
"Any reforms must ensure there's enough funding to support all children and pay staff properly for the work they do."
He added: "Ministers and schools must properly recognise and reward the vital role support staff play in delivering for children with SEND."
The National Association of Headteachers welcomed the "principle" of more support for pupils in mainstream schools and said "along with this significant investment, we will be scrutinising the details closely and speaking to school leaders to weigh up whether it is sufficient".
"There will always be some pupils whose needs are so great that they require support in a special school, and it's crucial the government's plans ensure all children get the support they need at the right time in the right setting," Paul Whiteman, general secretary of the union, said.
Jon Sparkes, chief executive of learning disability charity Mencap, said: "The move to make mainstream schools more inclusive is welcome news.
"Families must have their children's needs identified early and for them to be given the right help straight away, backed by services fully funded to do the job, and rights underpinned by law."
The Institute for Public Policy Research think tank said "no plan will be perfect" but that reforms to the system should not become the next "political flashpoint" in Westminster.
"The costs of delay are already being felt," associate director Avnee Morjaria said.
"This must now be a moment for everyone to get behind a serious programme of reform."