Rishi Sunak’s once close friend, Robert Jenrick, is leading the 64-strong Tory rebellion.
Boris Johnson was out of the traps this morning to throw his support behind the rebels.
Loyal MPs are spitting that two deputy party chairmen – Lee Anderson and Brendan Clarke-Smith – have put their names to rebel amendments and not yet been sacked.
Welcome to another day in the Conservative Party psychodrama.
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Boris Johnson moves against PM on Rwanda
Mr Jenrick, who abstained on the second reading of the Rwanda bill, went further than I thought he would on Tuesday in an interview with me, telling Sky News he was prepared to vote down the bill if the prime minister didn’t make robust changes to the proposed legislation.
His argument is consistent – he doesn’t believe the bill as it stands will work, and he – like Mr Sunak – is prepared to “do whatever it takes”.
“The government has a choice,” he added. “It can accept the amendments… or it can bring back a new and improved bill, and it can do that in a matter of days.”
When I point to concessions the government is offering – such as more judges and further streamlining the judicial process – Mr Jenrick is unmoved.
Neither is he being swayed by another argument the government is hammering home to rebels – that Rwanda won’t take any deportees if it deems the UK has broken any international law over this legislation.
“It is quite an implausible suggestion from the government, which was raised at the 11th hour,” he said. “I think it is a highly convenient argument…I don’t think it’s going to wash with colleagues.”
For his part, the prime minister argues he has gone as far as he can legally while staying on the right side of the law, while Mr Jenrick says he has not.
When I asked the former immigration minister whether he has legal advice showing that there is a respectable argument for these amendments that he’s privately shared with the government, he tells me he has the legal opinion but says it’s “not common practice” to share legal advice.
“The PM has said that his test is [for there to be] respectable legal arguments in favour of any amendments,” he said.
“I have a legal opinion from a highly respected lawyer, John Larkin Casey, the former attorney general of Northern Ireland, who attests to that fact.”
So, it appears the rebels and the government are at a standoff.
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Number 10 does not seem minded to budge, believing that it will, as with the second reading of this bill, be able to pick off rebels and get it passed.
Meanwhile, Mr Jenrick – alongside former home secretary Suella Braverman – is upping the ante by declaring they will, if necessary, vote down the legislation.
When I put it to the former immigration minister that it would, in effect, be a confidence issue in the prime minister and leave him in crisis should he lose the vote, he disagreed, arguing that what was at stake was getting the policy right.
But this argument won’t be lost on other rebels, worried that torpedoing the Rwanda legislation entirely will only make it worse at the ballot box, leaving the government with absolutely no chance of tackling the problem, while leaving an already diminished leader defenestrated.
For now, the consensus around Westminster is that the legislation will pass – although perhaps with a smaller majority than the 44 the prime minister secured at the second reading.
But it looks like it’s going to be messy and damaging.
If Mr Jenrick’s rebel amendment around individual claims is called today, the government will be caught up in the spectacle of whipping its MPs to vote down 60-plus rebels.
That’s perhaps the biggest rebellion – please correct me if I am wrong out there – since 91 Tory MPs defied a three-line whip on House of Lords reform in the coalition years.
A victory this week will be banked as a win and will allow Mr Sunak to kick the matter of small boats into the long grass (at least for a bit) and reset his focus to an issue a little more fertile for him – the economy.
But what happens, as Mr Jenrick asks, if, come August there are still thousands of people coming across in small boats?
There is a chunk of his party, particularly in those Boris Johnson-backing Red Wall seats, who believe success or failure at the ballot box rests on this single issue, which is why they are unbiddable.
That’s why winning the vote won’t bring peace for the prime minister and his party.