The timing of the announcement on the Rwanda scheme, which is estimated to cost more than £500m over five years, has prompted scorn Labour.

A party source said: “Is there any more blatant sign that [former immigration minister Robert] Jenrick was right about this all being symbolic before an election than this mad flurry of stories?

“The core substance though hasn’t changed. This is a tiny scheme at an extortionate cost and the criminal gangs will see through this con.”

Downing Street categorically denied this. The prime minister’s press secretary said: “From our part there isn’t really a day to lose when people are dying in the Channel having been induced into boats by gangs.