Critics claim London betraying British values by relocating people to Rwanda

The British government pledged to go ahead with flying asylum seekers to camps in Rwanda on Tuesday despite criticism of the policy from a wide range of political, religious, and civic groups and leaders.

Two legal challenges to stop the flights to Kigali failed, clearing the way for departure, but individual cases on behalf of those who are supposed to be on board meant that just hours before the plane was due to take off, it was unclear how many people would actually be on it.

A letter published in The Times newspaper and signed by 25 bishops of the Church of England said no attempt had been made to "understand the predicament" of those affected, and said the policy "should shame us as a nation …our Christian heritage should inspire us to treat asylum seekers with compassion, fairness, and justice, as we have for centuries".

The archbishop of Westminster, the highest-ranking representative of the Catholic church in England, also condemned the policy, as did senior Muslim clerics and rabbis, and even Prince Charles, who as a member of the royal family rarely comments directly on political issues, has reportedly called the idea "appalling".

There has also been a global backlash, with the United Nations' high commissioner for refugees, Filippo Grandi, calling the policy "all wrong, for so many different reasons".

The United Kingdom, he pointed out, is a signatory to the International Convention on Refugees, and he said trying to "export" the responsibilities that came with this status "runs contrary to any notion of responsibility and international responsibility-sharing".

In addition to moral outrage, there have also been questions raised over the practicality of the program.

Lucy Powell, shadow culture secretary for the opposition Labour Party, told Sky News that aside from the ethics of the issue, the policy made no economic sense.

"We think this policy is unworkable ... it's incredibly expensive," she said.

"It's going to cost possibly over a million pounds ($1.21 million) per unsuccessful or successful refugee going to Rwanda. And we do think it's unethical-and it's quite un-British actually.

"We've been known around the world as a safe haven for those genuinely fleeing persecution and war-it's been part of our make-up in this country for decades."

Launching the policy in a speech in April, Prime Minister Boris Johnson said the deal was "uncapped" and could potentially see Rwanda "resettle tens of thousands of people in the years ahead".

However, on the morning the first flight was scheduled to depart, Foreign Secretary Liz Truss told ITV News she was unable to say how many people would be on it, amid reports the number could be in single figures.

"I suspect there will be people on the flight; I don't have the exact numbers but we are determined to make sure we're following through on this policy," she said.

The small print of the deal also includes a clause for the UK to take refugees from Rwanda.

"The participants will make arrangements for the United Kingdom to resettle a portion of Rwanda's most vulnerable refugees in the United Kingdom, recognizing both participants' commitment toward providing better international protection for refugees," the deportation agreement said.

The Daily Mail quoted a source at the British Home Office as saying this would cover "a number in the tens, not hundreds" of people in Rwanda who already have refugee status, but that no limit is specified in the document.