Suella Braverman has warned the Conservative Party faces “electoral oblivion” in a Commons statement this afternoon.
This comes as the Government prepares new legislation to tackle issues with the Rwanda migration pact raised by the Supreme Court.
The former Home Secretary demanded the Government not introduce “yet another Bill destined to fail”, warning that doing so would “let our party die”.
Taking a swipe at Sunak’s missions in Government, one of which is “stop the boats”, she warned: “‘Crossings are down’ is not the same as ‘stopping the boats’.
She laid out five “tests” the Government must meet, including ensuring the Bill addresses the Supreme Court’s concerns about the safety of Rwanda and enabling flights before the next election by “blocking off all routes of challenge”.
Braverman also demanded the Bill “remedy deficiencies in the IMA to ensure that removals can take place within days of people arriving illegally”.
The fourth test was that the Bill must enable the administrative detention of illegal arrivals until they are removed.
Finally, she demanded the Government sit over Christmas to get the Bill passed.
Closing her statement to the House, she said: “All of this comes down to a simple question: who governs Britain?
“Where does ultimate authority in the UK sit? Is it with the British people and their elected representatives in Parliament? Or is it in the vague, shifting and unaccountable concept of ‘international law’.
“On Monday, the Prime Minister announced measures that start to better reflect public frustration on legal migration.
“He can now follow that up with a Bill that reflects public fury on illegal migration and that actually delivers on his pledge to stop the boats.
“It is now or never. The Conservative Party faces electoral oblivion in a matter of months if we introduce yet another Bill destined to fail. Do we fight for sovereignty or let our party die?
“I refuse to sit by and allow the trust that millions of people have put in us be discarded like an inconvenient detail.
“If we summon the political courage to do what is truly necessary, and to fight for the interests of the British people, then I am confident that we will regain their support.
“And, if the Prime Minister leads that fight, he will have my total support.”
Home Secretary James Cleverly announced a new treaty with Rwanda yesterday, which Rwanda’s foreign affairs minister Vincent Biruta said would “strengthen” the asylum processing system.
The Government will present a Bill on the issue this afternoon, GB News understands.
This comes amid mounting fury from MPs over migration, with Braverman having repeatedly criticised the Government’s approach to the issue.