Prime Minister Rishi Sunak has urged the House of Lords to pass his flagship Rwanda bill, as he warned peers not to “frustrate the will of the people”.
Giving a press conference after the legislation was approved by MPs, Mr Sunak said it was now up to the Lords to “do the right thing”.
But he declined to give a date for when flights carrying asylum seekers would take off to Rwanda.
The PM would only say he wanted this to happen “as quickly as possible”.
The bill, which seeks to revive the government’s plan to send some asylum seekers to the east African country, was passed by 320 to 276 votes in the House of Commons on Wednesday.
Although in the end only 11 Conservative MPs voted against the legislation as a whole, Mr Sunak still suffered his biggest rebellion since becoming prime minister when around 60 backed changes they said would toughen up the legislation.
The rebels argue the bill will not work in its current form as they believe flights will still be blocked by legal challenges.
The aim of the policy is to deter people from crossing the Channel in small boats, which Mr Sunak has made a key priority of his premiership.
However, Labour says it an expensive “gimmick”, which is unworkable and unlawful.
Before becoming law, the bill must be approved by the House of Lords, where it is expected to face strong opposition.
The Lords are unlikely to vote it down completely but they can propose changes which would delay its progress.
Crossbench peer Lord Carlile, a leading lawyer and former independent reviewer of terrorism legislation, described the bill as “a step towards totalitarianism”.
He told BBC Radio 4’s Today programme many peers would see it as “a step too far” and an “illegitimate interference by politics with the law”.
Mr Sunak urged peers to pass the bill unamended and as quickly as possible to get flights up and running, describing this as “an urgent national priority”.
“The treaty with Rwanda is signed and the legislation which deems Rwanda a safe country has been passed unamended in our elected chamber,” he said.
“There is now only one question. Will the opposition in the appointed House of Lords try and frustrate the will of the people as expressed by the elected House? Or will they get on board and do the right thing?”
Asked if he could guarantee flights would take off before the next general election, which is expected this year, Mr Sunak said: “I’ve been crystal clear that we want to do this as quickly as possible… and it’s now up to the House of Lords.”
Earlier, Home Office minister Chris Philp told BBC Breakfast the “target” was for flights to leave by the spring, with Mr Sunak also previously saying this is his aim.
However, the prime minister did not give a concrete date when asked by journalists at the press conference.
Peers are due to begin debating the Rwanda bill before the end of this month, with the most crucial votes held in early March, according to senior House of Lords sources.
After this, the legislation will enter “ping pong”, where the Commons and Lords try to reconcile their versions of the bill.
This is likely to involve the government trying to remove any changes inserted by the Lords.
If all goes to plan the bill should become law around mid-March.