Rishi Sunak’s Rwanda deportation bill will become law after peers eventually backed down on amending it, opening the way for legal battles over the potential removal of dozens of people seeking asylum. After a marathon battle of “ping pong” over the key legislation between the Commons and the Lords, the bill finally passed when opposition and crossbench peers gave way on Monday night. The bill is expected to be granted royal assent on Tuesday. Home Office sources said they have already identified a group of asylum seekers with weak legal claims to remain in the UK who will be part of the first tranche to be sent to east Africa in July. Sunak has put the bill, which would deport asylum seekers who arrive in the UK by irregular means to Kigali, at the centre of his attempts to stop small boats crossing the Channel. The home secretary, James Cleverly, said it was a “landmark moment in our plan to stop the boats”. In a video posted to social media, he said: “The safety of Rwanda bill has passed in parliament and it will become law within days. “The act will prevent people from abusing the law by using false human rights claims to block removals. And it makes clear that the UK parliament is sovereign, giving government the power to reject interim blocking measures imposed by European courts. “I promised to do what was necessary to clear the path for the first flight. That’s what we have done. Now we’re working day in and day out to get flights off the ground.” Denisa Delić, director of advocacy at International Rescue Committee UK, said on Monday: “Irrespective of today’s passage of the safety of Rwanda bill, sending refugees to Rwanda is an ineffective, unnecessarily cruel and costly approach. “Rather than outsourcing its responsibilities under international law, we urge the government to abandon this misguided plan and instead focus on delivering a more humane and orderly immigration system at home. “This includes scaling up safe routes, such as resettlement and family reunion, and upholding the right to seek asylum.” The Home Office has whittled the list down to 350 migrants who are deemed to pose the least risk of submitting successful legal challenges blocking their deportation. Lawyers have told the Guardian that they will prepare legal challenges on behalf of individual asylum seekers. They can challenge their removal on a case-by-case basis, which could lead to their being taken off a flight list. The bill allows challenges if a detainee faces a “real, imminent and foreseeable risk of serious irreversible harm if removed to Rwanda”. They must lodge an appeal within eight days of receiving a deportation letter. The Home Office would then be given several days to respond. If their appeal is rejected, the person claiming asylum will then be given seven days to lodge a final appeal to an upper tribunal court, which will decide their claim within a further 23 days. The deal will cost £1.8m for each of the first 300 deportees, the National Audit Office has confirmed. Matthew Rycroft, the most senior civil servant in the Home Office who has overseen the scheme for two years, previously told MPs he did not have evidence to show that it had a deterrent effect that would make it value for money. Home Office staff have privately warned that there is a risk of thousands of asylum seekers disappearing once removals begin, keen to avoid receiving notification that they are being sent to Kigali. skip past newsletter promotion Sign up to First Edition Free daily newsletter Our morning email breaks down the key stories of the day, telling you what’s happening and why it matters Enter your email address Sign up Privacy Notice: Newsletters may contain info about charities, online ads, and content funded by outside parties. For more information see our Privacy Policy. We use Google reCaptcha to protect our website and the Google Privacy Policy and Terms of Service apply. after newsletter promotion Earlier, MPs stripped out amendments to the bill inserted by the Lords. Crossbench and Labour peers said they would reinsert similar changes in a battle of wills. The government will not send those who are eligible under the Afghan Relocations and Assistance Policy (Arap) to Rwanda, a Home Office minister told peers during one of the many debates held on Monday evening. Lord Sharpe said: “Once this review of Arap decisions for those with credible links to Afghan specialist units has concluded, the government will not remove to Rwanda those who received a positive eligibility decision as a result of this review where they are already in the UK as of today.” Lord Browne, a Labour former defence secretary who had been leading calls for such an assurance, said: “The minister does not believe this to be a concession, it is to him a restatement of what he has been telling us for some time, but in a different form.” Meanwhile, leading lawyer and independent crossbencher Lord Anderson of Ipswich said of the Rwanda scheme: “Its benefits remain to be seen. Its costs will be measured, not only in money, but in principles debased: disregard for our international commitments, avoiding statutory protections for the vulnerable, and the removal of judicial scrutiny over the core issue of the safety of Rwanda.” The prime minister also disclosed that the first flights removing asylum seekers to Rwanda were planned to depart in 10 to 12 weeks, missing his original spring target. At a specially convened press conference on Monday morning, he said the government would “not let a foreign court” block flights to Rwanda and stressed that he would finally end the “legal merry-go-round” associated with deportation flights. “Enough is enough,” he said. “No more prevarication, no more delay. Parliament will sit there tonight and vote no matter how late it goes. No ifs, no buts. These flights are going to Rwanda.” Labour said Sunak was wrong to blame the party’s peers for delaying the Rwanda bill. Yvette Cooper, the shadow home secretary, said: “[The] Tories are the largest party in both Houses of Parliament and they could have scheduled the final stages of the bill a month ago but they voluntarily delayed it because they always want someone else to blame.”