MARY LOUISE KELLY, HOST:

Let's head overseas now. The British government's plan to send migrants seeking asylum in Britain to the East African nation of Rwanda is unlawful. That's according to judges with the Court of Appeal, who said they had concerns about the policy. From London, Willem Marx reports.

WILLEM MARX, BYLINE: Months in the making, the judgment delivered by Britain's lord chief justice, Lord Burnett, was clear.

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IAN BURNETT: There is a real risk that persons sent to Rwanda will be returned to their home countries, where they faced persecution or other inhumane treatment, when in fact they have a good claim for asylum. In that sense, Rwanda is not a safe third country.

MARX: This ruling represents a blow to the British government of Prime Minister Rishi Sunak that's fought for more than a year to implement this policy. Announced in the spring of 2022, the plan had intended that migrants who reached Britain by boat from France would face almost immediate deportation to Rwanda. Their claims for asylum could be examined there, and if successful, they'd be invited to stay and settle in Rwanda. But the judges decided that based on the evidence, the landlocked nation in East Africa some 4,000 miles from Britain had what they call deficiencies in its asylum system.

SOPHIE LUCAS: The agreement between the U.K. government and Rwanda and the assurances provided as part of this did not mitigate sufficiently against a real breach of fundamental human rights, namely the right to be free from inhuman and degrading treatment.

MARX: Lawyer Sophie Lucas at law firm Duncan Lewis represents seven individuals involved in the case who have been threatened with removal to Rwanda.

LUCAS: They will be incredibly relieved and cautiously optimistic, perhaps, that they can rebuild their lives here in the U.K. They've been through unimaginable trauma.

MARX: But Rishi Sunak and his fellow Conservatives in government have said they disagree with today's ruling and will seek to overturn it in Britain's Supreme Court, perhaps later this year. Interior Minister Suella Braverman said the government's promise to stop the boat crossings require fresh thinking, along with the new legislation it's currently championing in Parliament.

SUELLA BRAVERMAN: We've got an unsustainable problem that we need to fix. And whilst of course we are disappointed with the decision today, we will be putting in an application to seek permission to appeal the judgment very, very swiftly.

MARX: Earlier this week, her own ministry released a report that calculated the financial costs associated with the various options for new migrant arrivals. It estimated it would cost roughly $85,000 more per person for asylum claims to be processed in Rwanda rather than the United Kingdom. A Rwandan government spokesperson said they took issue with the ruling that their country was not safe for asylum-seekers and refugees, calling it, quote, "one of the safest countries in the world" that has been recognized for its, quote, "exemplary treatment of refugees." As the legal tussle continues, it means many more months of uncertainty for those caught in the middle, according to organizations working with them like Freedom From Torture, where Sile Reynolds is head of advocacy.

SILE REYNOLDS: It's incredibly difficult for us to provide clinical services to people in those kind of circumstances or for them to make any kind of progress in their rehabilitative journey when they have that threat hanging over their heads at all times.

MARX: In court, the judges had made clear they were passing no judgement on the policy's political merits, but this particular policy remains deeply polarizing for Britain's politicians, but also society as a whole. For NPR News, I'm Willem Marx in London. Transcript provided by NPR, Copyright NPR.