It comes as official estimates suggest 65,000 migrants are expected to arrive in the UK this year compared to the 45,000 who claimed asylum in 2022.
Suella Braverman , the home secretary, is said to have drawn up plans to curb illegal migration that would push the “boundaries” of international law, including removing the right of migrants to appeal their exclusion from the asylum system.
However, if the European Court of Human Rights in Strasbourg rules that Ms Braverman’s new legislation is unlawful, Mr Sunak is open to withdrawing from the ECHR, according to the Sunday Times.
A source close to Mr Sunak told the paper: “The PM has been clear he wants to introduce legislation that meets our international obligations. This bill will go as far as possible within international law. We are pushing the boundaries of what is legally possible, while staying within the ECHR.
“But if this legislation gets onto the statute book and is found to be lawful by our domestic courts, but it is still being held up in Strasbourg, then we know the problem is not our legislation or our courts.”
They added: “If that’s the case, then, of course, he will be willing to reconsider whether being part of the ECHR is in the UK’s long-term interests.”
The Braverman plan would only allow migrants to lodge an appeal after they have been deported, regardless of whether or not they come from somewhere on the Home Office’s “safe countries” list. The United Nations has previously warned that such plans would violate international law.
Former Labour lord chancellor, Lord Falconer of Thoroton, said on Sunday that he expected the courts would slap down the proposals, which would “put the government beyond the reach of the law”.
Senior figures say Mr Sunak is prepared to withdraw from the ECHR before the election if the European court blocks the plans. Mr Sunak could put withdrawal at the heart of their manifesto to draw a sharp line between the Tories and Labour.
On Times Radio, Tory MP Richard Graham – one of Mr Sunak’s trade envoys – said he was “not sure the word comfortable is where I’d be” when asked how he feels about the idea of pulling out of the ECHR.
The predicted increase in immigration is due to a large number of individuals from Central Asia, particularly Afghanistan, who are trying to migrate through Turkey and into Europe.
Last week, it was revealed 250 illegal migrants arrived from India across the English Channel by small boats in January alone, surpassing the total number of 233 migrants that came during the first nine months of last year. If this trend continues, the number of migrants could reach between 70,000 to 80,000 in the current year.
The prime minister previously made stopping small boats one of his five key pledges in office and recently declared his intention to “make sure that if you come to this country illegally, you are detained and swiftly removed”.
Polling data and Tory focus groups indicate that immigration is one of the top three concerns of the party’s voters, alongside the economy and the NHS.
The Home Office has been approached for comment.