LONDON — A British government plan to send some asylum seekers to Rwanda led to another day of legal wrangling on Tuesday, as a small number of them waited to hear if they would be aboard a jet bound for Africa later in the day.
Originally, dozens of people who had arrived in Britain from France were scheduled to be on the flight that is expected to leave on Tuesday night, though that number is thought to have been whittled down to around seven by legal challenges.
Several of those cases were being heard on Tuesday, raising the prospect that the passenger list could dwindle further. But the government still says it wants the plane to take off even with only a handful on board, despite the cost estimated by the British news media at as much as 500,000 pounds, or about $600,000, and in spite of protests, including from church leaders.
On Tuesday afternoon, the flight was still on track to leave Britain after the country’s Supreme Court refused to agree to stop the deportation of asylum seekers before a case against the government is heard in full next month. The government, however, promised that the claimant in the case would be returned to Britain if a future challenge proved successful.
Care4Calais, an aid group involved in the appeals, said that all four of its clients would be on the flight Tuesday night, after having their cases dismissed by a court.
The arrival of a small but steady number of asylum seekers on boats from France has been a growing political problem for Prime Minister Boris Johnson who, in 2016, led the campaign for Britain to leave the European Union, arguing that it would allow the country to “take back control” of its borders.
Relations with the French government have been tense after Brexit. And, with limited cooperation with the French authorities, Mr. Johnson’s government has searched for other ways to curb the arrivals that have become an embarrassing symbol of Britain’s failure to police its post-Brexit frontiers.
The British government announced in April that it had reached a deal with Rwanda that would allow the processing and settling of asylum seekers in the African country. In return, Britain would pay Rwanda 120 million pounds for economic development programs.
The deal has provoked fierce opposition in Britain for being unworkable and unethical, including from religious figures, civil servants and — according to the Times of London — from Prince Charles, the heir to the British throne.
Critics accuse Mr. Johnson, who narrowly survived a vote of no confidence last week, of deliberately stoking the issue for political advantage. They argue that even if very few asylum seekers are deported, the policy is intended to send a signal to voters that Britain is tough on those seeking to enter Britain by crossing the English Channel, many of them in small boats.
Liz Truss, Britain’s foreign secretary, told the LBC radio station that the flights should be seen in the larger context of illegal migration and of criminal gangs making money from bringing migrants into Britain.
The government, Ms. Truss said, needed to ensure “that if they are not on today’s flight, they are on subsequent flights. But fundamentally, we need to break the business model, and that is why we have to take this action.”
The debate over the Rwanda asylum plan comes at a time when immigration into Britain from non-European Union countries continues to rise.
Critics of the government say that British policy effectively criminalizes those who are trying to claim asylum, making it impossible for most genuine refugees to enter the country legally.
Last year, at least 27 people drowned while trying to make the dangerous journey across the English Channel, one of the world’s busiest shipping routes — and even that tragedy failed to deter more from trying to enter Britain on small boats.
In Rwanda, the deportation deal adds to efforts by President Paul Kagame to promote his country as a darling of donors, open to business and a partner in finding solutions to global migration. Mr. Kagame, 64, who came to power after the 1994 genocide, has fashioned himself as a visionary bent on tackling poverty, reducing corruption and raising the profile of women.
He has also sent Rwandan troops to keep peace in troubled neighboring states and taken in African refugees who had faced brutal conditions in detention centers in Libya.
Yet Mr. Kagame’s rule has been overshadowed by his government’s record on human rights, which drew concern even from the British government last year.
Civil society groups have accused Mr. Kagame of cracking down on opposition figures, muzzling the news media and carrying out enforced disappearances and torture. Rwanda — alongside China, Turkey and Iran — has also been listed as one of the top countries that carry out “aggressive campaigns of transnational repression” by Freedom House, a U.S.-based nonprofit group.
This included the sentencing of Paul Rusesabagina, the dissident whose actions during the genocide were portrayed in the Oscar-nominated movie “Hotel Rwanda.” In a letter reviewed by The New York Times, the State Department last month declared Mr. Rusesabagina, a permanent resident of the United States, as “wrongfully detained” by Rwanda.
Given this, the deportation deal with Mr. Johnson’s government risks legitimizing Mr. Kagame’s authoritarian streak, said Evan Easton-Calabria, a senior researcher at the Feinstein International Center at Tufts University.
The safety of the asylum seekers in Rwanda was also a concern, she said, adding that refugees had faced arrests, threats and killings there in the past. Nor is there any guarantee that those taken to Kigali, the capital, will stay there rather than trying to re-enter Europe via new routes. In the past, some of those moved to Rwanda under an Israeli plan left the country.
“There’s a real risk in letting these flights go ahead,” said Ms. Easton-Calabria, who has worked with refugees in Uganda. “The risk is that a lot of people will remain completely unassisted, completely traumatized in a country where they don’t have any connections and don’t know the language.”
The migrant deportations also come as Rwanda is engaged in a diplomatic standoff with the Democratic Republic of Congo, which accused Kigali of supporting the M23 rebel group that it is battling.
Stephen Castle reported from London, and Abdi Latif Dahir from Nairobi, Kenya. Cora Engelbrecht contributed reporting from London.