Angola, Namibia and the Democratic Republic of Congo will face visa sanctions, blocking their tourists, VIPs and business people from travelling to Britain if they do not improve co-operation on removals.
Ms Mahmood said: "In Britain, we play by the rules. When I said there would be penalties for countries that do not take back criminals and illegal immigrants, I meant it.
"My message to foreign governments today is clear: accept the return of your citizens or lose the privilege of entering our country."
The move was reportedly inspired by President Trump's homeland security secretary, Kristi Noem, who has overseen the mass deportation policy in the US, according to The Times.
Ms Mahmood will address the House of Commons today to lay out "the most sweeping reforms to tackle illegal migration in modern times", effectively since the Second World War.
Modelled on the Danish system, the aim is to make the UK less attractive for illegal immigrants and make it easier to deport them.
Under the plans, the home secretary will bring forward a bill to change how article 8 of the European Convention on Human Rights (ECHR), the right to family life, is applied in migration court cases.
The Home Office has said it's seen a rise in the use of rights-based appeals in recent years as a means of avoiding deportation.
The changes would see only those with immediate family in the UK, such as a parent or child, being able to use article 8 in future.
The home secretary, who has been in the job for 73 days, also plans to change the law so that multiple attempts to appeal against refusals for asylum will no longer be allowed.
Furthermore, refugees would face a 20-year wait before they can apply for permanent settlement.
The Home Office said the "golden ticket" deal has seen asylum claims surge in the UK, drawing people across Europe, through safe countries, on to dangerous small boats.
Under the proposals, refugee status would become temporary and subject to regular review, with refugees removed once their home countries are deemed safe.
Housing and weekly allowances would also no longer be guaranteed.
The shake-up also envisions the introduction of safe and legal routes to the UK in a bid to cut dangerous journeys across the Channel.
A new independent body - similar to one in Denmark - is planned to fast-track the removal of dangerous criminals, and last-minute appeals would be expedited.
Ms Mahmood has denied that her plans are "racist", instead describing them as a "moral mission".
She said illegal immigration was causing "huge divides" in the UK, adding: "I do believe we need to act if we are to retain public consent for having an asylum system at all."
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Speaking on Sunday Morning with Trevor Phillips, Ms Mahmood said she had observed how illegal migration had been "creating division across our country".
She added: "I can see that it is polarising communities across the country. I can see that it is dividing people and making them estranged from one another. I don't want to stand back and watch that happen in my country."
Prime Minister Sir Keir Starmer said: "Britain has always been a fair, tolerant and compassionate country - and this government will always defend those values.
"But in a more volatile world, people need to know our borders are secure and rules are enforced. These reforms will block endless appeals, stop last-minute claims and scale up removals of those with no right to be here."
Conservative Party leader Kemi Badenoch welcomed Ms Mahmood "finally talking seriously about tackling illegal immigration", but called the plans "weak".
She said: "If the home secretary actually wants to cut illegal immigration, she should take up my offer to sit down with her and work on a plan that will actually stop the boats, rather than a few weak changes that will meet the approval of Labour MPs."
Speaking earlier on Sunday, Reform UK leader Nigel Farage said: "The home secretary sounds like a Reform supporter."
"Sadly with the Human Rights Act and ECHR membership, the changes won't survive the courts or probably even her own backbenchers," he added.
The Refugee Council warned that the government would accrue a cost of £872m over 10 years as a result of the need to review asylum seekers' status to remain in the UK.
Enver Solomon, the charity's chief executive, insisted the changes "will not deter people from making dangerous crossings, but they will unfairly prevent men, women and children from integrating into British life".
Latest Home Office figures show 39,075 people have arrived in the UK after crossing the English Channel in small boats so far this year.
The arrivals have already passed the number for the whole of 2024 (36,816) and 2023 (29,437), but the number is below the total for 2022 (45,774).
In an email to staff, Mr Shah said: "There is a lot being written, said and speculated upon about the possibility of legal action, including potential costs or settlements.
"In all this we are, of course, acutely aware of the privilege of our funding and the need to protect our licence fee payers, the British public.
"I want to be very clear with you - our position has not changed. There is no basis for a defamation case and we are determined to fight this."
It comes after the US president confirmed on Saturday he would be taking legal action against the broadcaster over the editing of his speech on Panorama - despite an apology from the BBC.
"We'll sue them. We'll sue them for anywhere between a billion (£792m) and five billion dollars (£3.79bn), probably sometime next week," he told reporters.
"We have to do it, they've even admitted that they cheated. Not that they couldn't have not done that. They cheated. They changed the words coming out of my mouth."
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The staggering levels of child poverty here also feel like they belong in a different time.
Six out of every seven children in Newport are classified as living in poverty.
The measure is defined by the Child Poverty Action Group as a household with an income less than 60% of the national average.
More than half of children across the whole of the constituency of Middlesbrough and Thornaby East are growing up in poverty.
As a long-awaited new strategy on child poverty is expected from the government, much of the focus on tackling the problem has been placed on lifting the two-child cap on benefits for families.
Researchers say there is direct link between areas with the highest rates of child poverty and those with the highest proportion of children affected by that two-child cap.
Mother-of-three Gemma Grafton said: "Maybe if families do have more than two children, give them that little bit of extra help because it would make a difference."
Three months ago, she and partner Lee welcomed baby Ivie into the world. With two daughters already, the cap means they receive no additional universal credit.
"You don't seem to have enough money some months to cover the basics," said Lee.
"Having to tell the kids to take it easy, that's not nice, when they're just wanting to help themselves to get what they want and we've got to say 'Try and calm down on what you're eating' because we haven't got the money to go and get shopping in," added Gemma.
The couple had to resort to paying half of the rent one month, something they say is stressful and puts their home at risk.
Those who work in the area of child poverty say they are engaged in a battle with child exploitation gangs who will happily step in and offer children a lucrative life of crime.
"Parents are crying that they're failing because they can't provide for their children," said Tracey Godfrey-Harrison, project manager at the Middlesbrough Food Bank.
"In today's society, it's disgraceful that anyone should have to cry because they don't have enough."
In the shadow of a former steelworks, Dormanstown Primary Academy serves pupils in a community hit hard by the economic collapse that followed.
The school works with charities and businesses to increase opportunities for pupils now and in the future.
Katrina Morley, the academy's chief executive, said: "A child who hasn't been able to sleep properly can't concentrate. They're tired. We know that the brain doesn't work in the same way. A child who is hungry can't access the whole of life.
"When you face hardship, it affects not just your physiology but your emotional sense, your brain development, your sense of worth. They don't get today back and their tomorrow is our tomorrow."
The school's year six pupils see the value of things like the on-site farm shop for families in need.
They are open about their own worries, too.
Bonnie, 10, said: "I think that's very important because it ensures all the people in our community have options if they're struggling.
"It can be life-changing for families in poverty or who have a disadvantage in life because they don't have enough money and they're really struggling to get their necessities."
Mark, also 10, said: "I worry about if we have nowhere to live and if we haven't got enough money to pay for our home. But at least we have our family."
They also see the homelessness in the area as the impact of poverty. "I think it actually happens more often than most people think," said Leo, "because near the town, there's people on the streets and they have nowhere to go."
The school is one of many calling for the lifting of the two-child cap.
The need for life's essentials has prompted more than 50 families to register for help at Barney's Baby Bank in the last 11 months. Nappies, wipes, clothing, shoes, toys, are a lifeline for those who call in.
Founder Debbie Smith said local people "are struggling with food. They're obviously struggling to clothe their babies as well. It's low wages, high unemployment, job insecurity and that two-child benefit cap".
"Middlesbrough does feel ignored," she added.
A government spokesperson said: "Every child, no matter their background, deserves the best start in life. That's why our Child Poverty Taskforce will publish an ambitious strategy to tackle the structural and root causes of child poverty.
"We are investing £500m in children's development through the rollout of Best Start Family Hubs, extending free school meals and ensuring the poorest don't go hungry in the holidays through a new £1bn crisis support package."
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But what is the message to those making the decisions from the North East?
"Come and do my job for a week and see the need and the desperation the people are in," said Ms Godfrey-Harrison. "There needs to be more done for people in Middlesbrough."
It follows a months-long trial in the country that found her guilty of ordering a deadly crackdown on a student-led uprising last year.
The former leader, exiled in India, was tried in absentia after the United Nations said up to 1,400 people may have been killed in the violence.
Bangladesh's health adviser under the interim government said more than 800 people were killed and about 14,000 were injured.
The students initially started protesting over the way government jobs were being allocated, but clashes with police and pro-government activists quickly escalated into violence.
The court revealed conversations of Hasina directing security officers to drop bombs from helicopters on the protesters.
She also permitted the use of lethal weapons, including shotguns at close range for maximum harm, the court was told.
Hasina, who previously called the tribunal a "kangaroo court", fled to India in August 2024 at the height of the uprising, ending 15 years of rule.
In a statement released after the verdict, Hasina said the ruling was "biased and politically motivated" and "neither I nor other political leaders ordered the killing of protesters".
"I am not afraid to face my accusers in a proper tribunal where evidence can be weighed and tested fairly," she added.
The 78-year-old is the daughter of Sheikh Mujibur Rahman, who led the country to independence.
The International Crimes Tribunal, Bangladesh's domestic war crimes court located in the capital Dhaka, delivered its four-hour verdict amid tight security.
Hasina received a life sentence under charges for crimes against humanity and the death sentence for the killing of several people during the uprising.
The packed courtroom cheered and clapped when the sentence was read out.
The tribunal also sentenced former home minister Asaduzzaman Khan - also exiled in India - to death.
A third suspect, a former police chief, was sentenced to five years in prison as he became a state witness against Hasina and pleaded guilty.
The ruling is the most dramatic legal action against a former Bangladeshi leader since independence in 1971 and comes ahead of parliamentary elections expected to be held in February.
Foreign ministry officials in Bangladesh have called on India to hand over the former prime minister, adding it was obligated to do so under an existing treaty between the two nations.
India's foreign ministry said it had noted the verdict concerning Hasina and "remained committed" to the people of Bangladesh, the Reuters news agency reported.
"We will always engage constructively with all stakeholders to that end," the ministry added in a statement.
During the verdict, protesters had gathered outside the former home-turned-museum of Hasina's late father demanding the building be demolished.
Police used batons and stun grenades to disperse the crowd.
Paramilitary border guards and police have been deployed in Dhaka and many other parts of the country, while the interim government warned any attempt to create disorder will be "strictly" dealt with.
Hasina's Awami League party called for a nationwide shutdown in protest at the verdict.
The mood in the country had been described as tense ahead of Monday's ruling.
At least 30 crude bomb explosions and 26 vehicles were set on fire across Bangladesh during the past few days.
Local media said two people were killed in the arson attacks, according to the Associated Press.
Hasina is also the aunt of former UK government minister, Tulip Saddiq, who resigned from her Treasury job at the start of this year.
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Ms Siddiq had faced calls to step down over links to her aunt and was also said to be facing a corruption trial in Bangladesh.
She told Sky News in August the accusations were "nothing more than a farce" and said she had never been contacted by the Bangladeshi authorities.
The opening of the inquest into Jonte William Bluck's death heard he was bitten by a family dog while staying at his father's home in Crossway, Rogiet, Monmouthshire, on 2 November.
A provisional cause of death was given as a compressive head injury, consistent with a dog bite.
Area coroner Rose Farmer said: "Jonte William Bluck sadly passed away on the 2nd of November 2025 at his home address.
"The brief circumstances are that on the 2nd of November he was staying at the home of his father when he was bitten by the family dog.
"He was conveyed to the Grange University Hospital but died prior to arrival.
"An inquest has been opened as there is reason to suspect that he died as a result of a dog bite."
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The dog involved in the incident was a six-year-old XL bully, which was registered with the Department for Environment, Food & Rural Affairs (Defra) and a certificate of exemption was issued in 2024.
It was put down following the incident.
The inquest into the baby's death was opened at Gwent Coroner's Court on Monday but adjourned until 4 August next year, while police inquiries continue.
Following the baby's death, a man in his 30s and a woman in her 20s from Rogiet were arrested on suspicion of being in charge of a dog dangerously out of control, causing injury resulting in death.
Both were also arrested on suspicion of child neglect. They were later released on police bail as inquiries continue.