Rishi Sunak is facing fresh pressure over his Rwanda policy after it emerged the scheme has already cost £240m, despite never being used.
The government spent a further £100m in the 2023-24 financial year while flights remained grounded amid a series of legal setbacks – on top of the £140m previously paid out.
According to a letter from the Home Office to committee chairs, ministers expect additional costs of £50m in the coming year, which would bring the total to £290m.
It comes just hours after Mr Sunak vowed to “finish the job” of reviving his plan to deport some asylum seekers to Kigali – despite the prospect of a bitter parliamentary battle.
Home Office official Matthew Rycroft wrote to Home Affairs Committee chair Dame Diana Johnson, and Public Accounts Committee chair Dame Meg Hillier, on Thursday.
His letter said: “Ministers have agreed that I can disclose now the payments so far in the 2023-24 financial year.
“There has been one payment of £100m, paid in April this year as part of the Economic Transformation and Integration Fund mentioned above.
“The UK government has not paid any more to the government of Rwanda thus far.
“This was entirely separate to the treaty – the government of Rwanda did not ask for any payment in order for a treaty to be signed, nor was any offered.”
Labour described the revelation as “incredible” – with shadow home secretary Yvette Cooper saying: “How many more blank cheques will Rishi Sunak write before the Tories come clean about this scheme being a total farce?
“Britain simply can’t afford more of this costly chaos from the Conservatives.”
The government hopes to rush emergency legislation through parliament for MPs and peers to declare that Rwanda is a safe destination for asylum seekers.
Mr Sunak earlier insisted his new law would end the “merry-go-round of legal challenges”.
In the Commons, Tory right-wingers may seek to beef up the bill by calling for it to effectively override international law.
MPs will get their first chance to debate and vote on the Safety of Rwanda (Asylum and Immigration) Bill on Tuesday.
The prime minister dismissed suggestions he will make it a confidence vote, meaning that MPs would have the whip withdrawn if they defied him.
Under the government’s plan first unveiled in April 2022, people who arrive in the UK by irregular means – such as on small boats – could be sent on a one-way trip to Rwanda, where the Kigali government would decide on their refugee status.