The government has already admitted that its Illegal Migration Bill may breach human rights law, with the prime minister saying he was “up for the fight” that is predicted to take place over the matter in British courts.
The bill would impose a legal duty on the home secretary to remove anyone who arrives on a small boat, either to Rwanda or another “safe third country”, without hearing their asylum claim.
In a statement issued on Tuesday afternoon, the UNHCR said such legislation would “amount to an asylum ban ... no matter how genuine and compelling” individual cases may be.
“The effect of the bill would be to deny protection to many asylum seekers in need of safety and protection, and even deny them the opportunity to put forward their case,” the agency added.
“This would be a clear breach of the Refugee Convention and would undermine a long-standing, humanitarian tradition of which the British people are rightly proud. We urge the government, and all MPs and peers, to reconsider the bill and instead pursue more humane and practical policy solutions.”
Earlier, Suella Braverman was jeered as she told parliament she would not address the law’s “full legal complexities” and admitted that the “robust and novel” plans may not comply with the Human Rights Act.
In a separate letter to MPs, the home secretary wrote: “This does not mean that the provisions in the bill are incompatible with the convention rights, only that there is a more 50 per cent chance that they may not be.”
Mr Sunak was bullish about the prospect of legal challenges, batting away questions put to him at a press conference about practical issues pertaining to Britain’s capacity to detain and deport large numbers of asylum seekers.
He said there was “absolutely nothing improper or unprecedented” about pursuing laws that might violate the Human Rights Act, and that he and his government “believe we are acting in compliance with international law”.
Mr Sunak said, without providing evidence, that the new law would “deter” people from crossing the Channel in small boats, and that it would allow the UK to “decide who we bring here and how many”.
More than 3,000 people have crossed the Channel so far this year – double the 1,500 seen by the same point in 2022, which was itself a record year.
The UNHCR said that Home Office data – which shows that in terms of nationality, Afghans account for the largest number of those currently making the journey – indicates that the “vast majority” of small-boat migrants would be granted refugee protection if the UK considered their claims.
“Branding refugees as undeserving based on mode of arrival distorts these fundamental facts,” the agency added, calling on the government to consider its own “concrete and actionable proposals” as a way to reduce the demand for small-boat crossings.
In speeches unveiling the bill, the home secretary and prime minister accused boat migrants of “jumping the queue” and violating “fairness”, saying that refugees should only arrive on routes that are chosen by the government and subject to a numbers cap.
But the UNHCR said resettlement programmes “remain very limited and can never substitute for access to asylum”, which people must currently be present in the UK to claim.
The body said the plans undermine the “very purpose” of the 1951 Refugee Convention, which was approved at the time by all parties in the House of Commons after being ratified by Winston Churchill’s Conservative government.
“The convention explicitly recognises that refugees may be compelled to enter a country of asylum irregularly,” the statement added. “International law does not require that refugees claim asylum in the first country they reach.”
The UNHCR said that while it is possible to transfer asylum seekers between safe third countries, the UK is “not part of any such agreement” and the Rwanda deal fails to meet the necessary international standards.
Yvette Cooper, the shadow home secretary, accused the government of worsening the “deeply damaging chaos” in the Channel with a failure to tackle people-smuggling gangs, “collapsing” asylum decisions, and a falling number of family reunion visas.
“The asylum system is broken and they broke it,” she added. “They still don’t have any return agreements in place ... this bill isn’t a solution, it’s a con that risks making the situation worse.”
The Rwanda scheme has failed to start, having been beset by legal challenges, and Albania is the only other nation to have agreed to accept asylum seekers from the UK, after an EU-wide mechanism was lost during the Brexit process.
The UK’s immigration detention estate is not big enough to hold a significant proportion of small-boat migrants awaiting deportation, and crossing the Channel to claim asylum was only made illegal on 28 June 2022.
Opposition MPs accused the government of abandoning Afghans who had not managed to board evacuation flights out of Kabul in August 2021. Ms Cooper said that those who attempt to make their own way to the UK “will only ever be illegal in the eyes of a government who relied on the sacrifice they made”.
Tory MPs have told The Independent they are concerned that the government will struggle to pass the legislation, or bring it into effect, before the next general election, especially if Theresa May makes an intervention.
One said he was pressing ministers to get more returns agreements with other countries, adding: “I know we have this deal with Albania, but if we had actually sent loads of people back there I would be shouting about it from the rooftops.”
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