Rishi Sunak’s proposed Rwanda asylum law has cleared its first major hurdle in the House of Lords, but faces a bruising ride as the Archbishop of Canterbury warned it is “leading the nation down a damaging path”.

In a withering rebuke to the scheme to send asylum seekers who cross the Channel in small boats on a one-way flight to Kigali, the Most Rev Justin Welby accused the Government of outsourcing the country’s “legal and moral responsibilities” and signalled he may yet seek to block it.

The top Anglican cleric also argued “a pick-and-choose approach to international law” undermined the UK’s global standing.

A barrage of criticism was levelled at the Government’s Safety of Rwanda (Asylum and Immigration) Bill, during its lengthy second reading debate in the upper chamber, with accusations that it was immoral, repugnant and an attempt to “legislate a lie”.

A pick-and-choose approach to international law

It even saw Tory grandee Ken Clarke warn over the risks of moving the UK towards an “elective dictatorship”.

But ministers argued that the Bill was “the moral course” and “the humane thing to do”.

The controversial draft legislation seeks to address the legal challenges which have dogged the stalled policy by compelling judges to regard the east African country as safe, while giving ministers the power to ignore emergency injunctions.

While the Bill survived a Liberal Democrat-led bid to derail it, the unelected chamber is certain to seek numerous changes, putting them on a collision course with the Tory administration and an extended tussle between the Commons and Lords during “ping-pong”.

The Prime Minister had warned peers against blocking “the will of the people” by frustrating the passage of the legislation ahead of an election, having made “stopping the boats” a key pledge of his leadership.

Speaking during the debate, Mr Welby said: “We can, as a nation, do better than this Bill.

“With this Bill the Government is continuing to seek good objectives in the wrong way, leading the nation down a damaging path.”

If we don't think international law matters, what are we doing in Ukraine? What are we doing in the Red Sea with respect to the Houthis?

He added: “Rwanda is a country I know well, it is a wonderful country and my complaint is not with Rwanda, nor with its people. It has overcome challenges that this House cannot begin to imagine.

“But this Bill continues, wherever it does it, to outsource our legal and moral responsibilities for refugees and asylum seekers, with other countries far poorer already supporting multitudes more than we are now and to cut back on our aid.”

He said: “The UK should lead internationally as it has in the past, not stand apart.

“A pick-and-choose approach to international law undermines our global standing and offends against the principle of universality that is their increasingly threatened foundation.”

Given the Lords is a revising chamber, Mr Welby said “sadly” he would not back the move to block the Bill at second reading, although he found the argument for it “convincing and powerful”.

He pointedly added: “But I think we have to wait until third reading and have done our revising work.”

Labour frontbencher Lord Coaker warned the Government over flouting international law.

He said: “If we don’t think international law matters, what are we doing in Ukraine? What are we doing in the Red Sea with respect to the Houthis?”

He added: “If international law and conventions don’t matter, and you can disregard them when you want, what does that say for the international rules-based order?”

Home Office minister Lord Sharpe of Epsom said: “Stopping illegal migration is an important issue for both the public and this Government. Parliament and the British people want an end to illegal migration and therefore we need a deterrent.

“The Archbishop of Canterbury and other members were right to place this Bill in its moral context but proceeding with this Bill is the moral course.

“We must put a stop to the dangerous Channel crossings that are putting lives at risk and we must put an end to this mass trafficking of people to save lives. That is the humane thing to do and it is the fair thing to do.”

Meanwhile, the Equality and Human Rights Commission (EHRC) has warned the Bill risks the UK breaching its obligations under international law.

It argued the draft legislation “undermines the universality of human rights” and in doing so “could expose people to harm and breaches of their right to life, their rights to be free from torture and inhuman or degrading treatment and their right to effective remedy”.

The number of migrants who made unauthorised Channel crossings of the Channel this year passed 1,000 after more than 300 made the journey at the weekend.

The asylum scheme comes with a £290 million bill but a series of legal challenges has meant no flights have taken off since it was first proposed in 2022, when Boris Johnson was in Number 10.

Under the plan, people who cross the Channel in small boats could be removed to Rwanda rather than being allowed to seek asylum in the UK.

The legislation, along with the recently signed treaty with Kigali, is aimed at ensuring the scheme is legally watertight after the Supreme Court ruling against it last year.