Rishi Sunak is facing one of the biggest days in his short premiership thus far as he tries to convince his own Tory MPs to back his Rwanda bill ahead of a key vote.
After a frantic end to Boris Johnson's time as Prime Minister, and a chaotic few weeks with Liz Truss at the helm, it was hoped that Sunak, seen by many as a 'safe pair of hands', would add some much-needed stability back to an increasingly divided Conservative Party.
But now, Sunak's flagship policy could be the first bill to be defeated in the Commons during its first vote since 1985.
Former defence secretary Ben Wallace is urging his party not to "wreck" the government by voting the policy down as some Tory MPs claim there's a "real possibility of defeat".
A 'Rubik's cube' of a problem
Writing for The Telegraph, the former North-east MSP said: "Before anyone in my party thinks the solution to this Rubik’s cube is to wreck the Government, perhaps we should calmly state that we are heading in the right direction and making progress."
Mr Wallace added: "Next comes Rwanda. Yes, we lost before the courts, but just like any government before us, we have addressed the issues and I am confident that, as long as Labour doesn’t use the unelected House of Lords to derail the scheme, there is a good chance the return programme will progress.
"Conservative MPs must not let Keir Starmer off the hook by turning [Tuesday’s] vote into an exercise of making the perfect (but unrealistic) the enemy of the good. Strong deterrence has to be built brick by brick."
Many right-leaning Conservatives - who are reportedly meeting with the Prime Minister on Tuesday morning ahead of the vote - claim the bill doesn't go far enough, including former immigration minister Robert Jenrick, who resigned last week.
However, Home Secretary James Cleverly argues they are "mistaken".
He said: "The protections in the treaty as well as the content of the Bill mean that MPs have no good reason not to express their collective view that Rwanda is safe by voting for the Bill.
"Meanwhile, those who say that the Bill doesn’t go far enough are, with all due respect, mistaken. And the way to prove that it cannot work is not to make sure that it cannot work."
But centrist Tory MPs have raised concerns of their own about future amendments that may result in "government breaching the rule of law and its international obligations".
Chairman of the One Nation group and former deputy prime minister Damian Green urged the government to "stand firm against any attempt to amend the bill in a way that would make it unacceptable to those who believe that support for the rule of law is a basic Conservative principle".
Opposition parties have already said they will vote against the bill, meaning Sunak faces a challenge to unite all sides of his party in an effort to jump the first hurdle, in what is potentially a career-defining vote for his premiership.