Laura Kuenssberg: Can the rebel alliance stop no-deal Brexit?

Philip Hammond and Jeremy Corbyn Image copyright PA/EPA
Image caption Opposition to Mr Johnson has made unlikely political allies

It doesn't take long to find outrage around here - genuine or confected.

That's been the case for as long as the arguments about Brexit have been raging, longer than many of us might care to remember.

But, as one senior minister suggested tonight, for the rebels ranged against Boris Johnson next week, being angry about the time they have at hand isn't going to achieve their goals. "The thing for them is not to be outraged, it's to change the law."

Within days we will know if the MPs who are implacably opposed to leaving the EU without a deal can really do that.

With lots of former ministers on the backbenches, the group which is openly fighting against the possibility of leaving the EU without a deal has a different complexion.

And the opposition parties, including the Labour leadership, now appear fully engaged in next week's plan.

This is a big, powerful and diverse group, rather than a handful of experienced backbenchers doing their best to get huge numbers of MPs on side.

The strange political rainbow that is the loose rebel alliance now ranges from Conservatives like Philip Hammond at one end, all the way through to Jeremy Corbyn on the other - from dark blue to dark red, taking in yellow, green and all sorts of other shades in the middle.

Brexit continues to do weird things to the shape of our politics.

They are united in a determination to make it impossible for the prime minister ever to take us out of the EU if he hasn't been able to agree a new deal with the EU, or get one that's approved by Parliament.

It's a broadly held fear that leaving without formal arrangements in place could cause havoc - politically, and for the economy.

But given Boris Johnson's main reason for success in the Tory leadership election was to leave the EU whatever it takes at the end of October, it is a pretty major goal for a group of backbenchers and opposition politicians.

Politically charged

It's not just a demand to tweak a policy here or there, but to put a block on a vital part of the new PM's plan.

To do it, they are essentially trying to pull off the same trick as before, when, breaking convention, Yvette Cooper - along with other former ministers like Nick Boles and Oliver Letwin - led an unprecedented charge.

Using emergency procedures, MPs took control of what gets voted on and discussed in the Commons, and passed - by only one vote - a measure to force Theresa May to delay Brexit, rather than leave with no deal.

You can read more about it here for a refresher.

In truth Mrs May was, by then, extremely unlikely to leave without a deal, so it was dramatic and important, but much less politically charged than what we'll see next week.

Because the prime minister this time is openly committed to taking us out, whatever happens, in two months' time.

'No guarantee'

Talking to MPs involved this time, the plan is "well evolved", but there are still live discussions about the exact wording this time round.

I'm told the length of any extension and the kind of deadline they might seek to apply are still under consideration, the dates are very fluid and very sensitive.

One of those involved, Chris Leslie, told us today the vote might just in fact be to force Mr Johnson to give Parliament a vote on authorising a no-deal departure so it was not a decision he could make on his own.

He said: "By the time we get to Tuesday there will be, I believe, a proposal to put in protections against crashing out with no deal.

"That could mean we simply ensure that the House of Commons has to authorise whatever happens after 31 October. It may well be that there is a requirement on the prime minister to extend beyond."

Mr Leslie is confident that the group will have enough support. But others are not so sure.

Former Justice Secretary David Gauke - whose name has given the new Tory rebels the nickname of the 'Gaukeward squad' (don't blame me, it wasn't my gag to start with) - is one of those.

He told us today that "there is no guarantee", even though he fears next week might be the "last chance" if Parliament is going to assert itself.

Media playback is unsupported on your device
Media captionDavid Gauke: "There isn't a mandate for no-deal Brexit"

Clearly there are plenty of newly emboldened Conservatives, freed from the constraints of government, who are ready and willing to vote against their leader next week.

But remember, it's not just about them, but the opposition parties too.

Although the Labour leadership seems nailed on to back the effort, they can't be sure all of their MPs will follow that line.

As ever, there are nerves among MPs about going against their constituents. There are some Labour MPs who hate the idea of leaving the EU, and no deal, but do not want to be seen to be part of stopping it happening, or creating yet another delay.

With numbers pretty tight, their decisions next week will be vital. One of the MPs who has been galvanizing the effort told me "the most important determinant is whether Labour MPs with constituencies that voted Leave can be persuaded."

That MP guessed that if more than 20 Labour MPs vote against or abstain when it comes to the votes, then the attempt overall will fail.

Relishing the fight

There is also the simple question of whether there is enough time on the clock to get it done, including whizzing through the House of Lords.

The sleeping bags are on standby for the possibility of all-night sittings.

Some MPs may try to insist they hold votes and debates all through the weekend to get it done.

There is a sense in some parts of government that Number 10 might actually relish this fight.

It's a chance for Mr Johnson's backers to make the already familiar case that he's on the side of people who just want what they voted for, and who don't want to be messed around any more by pesky Parliamentarians.

But ministers will fight hard to win next week for if they lose, it's a big rock in the prime minister's road to getting Brexit done. Whether Number 10 would ultimately pay any attention is a different question for another day.

Stand by, though, for the first huge showdown between the new prime minister and Parliament.

The Commons officially opens again for business next Tuesday at 14:30 BST. A key figure involved told me to get this going, "I'll be there at 2.31pm".

The strange political family fighting Mr Johnson doesn't have much time to lose, and a huge argument to try to win.