Here's what might happen...

But what happens after that? Read more here.

Nigel Farage says if Boris Johnson and the Conservatives are "even contemplating" trying to pass a form of Theresa May's withdrawal agreement "we will fight them every inch of the way".

However he says if the prime minister holds a general election to ask for "a mandate for us to leave with a clean Brexit, then we in the Brexit Party will put country before party and do everything to help Mr Johnson".

The Brexit Party leader Nigel Farage is now talking at a party event.

"I think what is happening in our country today is something that the generations who went before us would never have believed," he tells the audience.

"We were given a full free and fair referendum, we had politicians who promised to implement the result, but now we have a Parliament which is doing its damnest to stop it from happening.

"We even have senior figures like Jeremy Corbyn supporting active street protest - we are heading towards mob rule."

"Someone has to stand up for democracy and decency."

Speaking about the prime minister's statement this evening, Labour leader Jeremy Corbyn tells supporters at a rally: "What Boris Johnson was doing was essentially threatening people. Threatening people with a no-deal Brexit if he doesn't get his way in Parliament."

"We will challenge them in Parliament tomorrow, and we will continue that challenge," he says.

There's less than two months before the UK is due to leave the EU. So what might happen next?

The BBC's senior elections and political analyst Peter Barnes runs through the options here.

Douglas Carswell was a Conservative MP until 2014 when he defected to the UK Independence Party.

He stood down from Parliament in 2017.

Labour leader Jeremy Corbyn says Boris Johnson's statement "didn't amount to very much".

"In fact it amounted to almost nothing at all," he tells Labour supporters at an event in Salford.

"Except there was quite a powerful subliminal message there. As with the years of Theresa May, it's all about the Tory Party. It's the Tory Party talking to the Tory Party about the Tory Party and the Tory Party's opportunities for the future."

It is understood Jeremy Corbyn will host leaders of opposition parties tomorrow morning for a further meeting on blocking a no-deal Brexit ahead of the attempt in Parliament to take control of the order paper.

The meeting will take place in the Leader of the Opposition's offices.

Attendees of the meeting will include:

• SNP Westminster leader Ian Blackford
• Green Party MP Caroline Lucas
• Shadow chancellor John McDonnell

• Plaid Cymru Westminster leader Liz Saville Roberts
• Independent Group for Change leader Anna Soubry
• Lib Dem Leader Jo Swinson

Katya Adler
Europe Editor

As the UK steels itself for a week of edge-of-yer-seat high political drama, what do our "negotiating partners" in the EU make of it all?

I use inverted commas for "negotiating partners" because, despite UK government assertions, there are no real EU-UK negotiations currently taking place.

Truth be told, EU leaders are pretty open-mouthed at what's going on across the Channel.

A cabinet minister in Finland, meanwhile, described himself as so gobsmacked by the idea that Prime Minister Boris Johnson will suspend parliament at such a time of political crisis, that he likened it to the Finnish government trying to announce a national ban on saunas (which they aren't intending to do, by the way).

Read Katya's blog in full here.

The government is expected to table a motion to hold a general election on 14 October if MPs vote to take control of business in the House of Commons tomorrow.

Jessica Parker
BBC political correspondent

What you've seen out of this administration so far is they are not shy of confronting people and causing a bit of a stir.

Whether that is suspending Parliament unexpectedly for up to five weeks; whether it is this message that's come through over the weekend that Conservative MPs who don't back the government could lose the party whip and therefore not be able to stand at the next election.

Certainly the tone from Downing Street has been a tough one.

What you're seeing from this administration is a real willingness to try and take people on, but it's not without risk - sometimes rather than bring people back in, it can push people away.

Image source, UK Parliament

Shadow home secretary Diane Abbott is speaking at a Labour rally in Salford.

"We are here today at a pivotal political moment... and it's not about Brexit, it is not about whether you voted to leave or remain, it's about what sort of country you want this to be," she says.

She describes Mr Johnson as a "rotten prime minister" adding "the sooner we get him out the better."

She adds: "We know we are closer to power now than we ever have been and we have got the fight of our lives on our hands because every tool in Boris Johnson's box, he will pull out."

Nick Boles resigned from the Conservative Party in April, accusing his party of failing to "compromise" over Brexit.

BBC News Channel

Senior Conservative backbencher Charles Walker says a general election is "inevitable at some stage in the very near future".

The pro-Brexit MP says he is not in favour of the deselection of Tory MPs who rebel over Brexit: "It is just no good continuing to have a divided party that is falling out over the EU."

"We've had a miserable 12 months and I don't want to have another miserable few months ahead of us."

Image source, EPA

The prime minister is making "a historical mistake", says the Brexit Party leader Nigel Farage speaking on LBC Radio.

He says Boris Johnson "wants Mrs May's withdrawal agreement, but minus the backstop".

That, Mr Farage argues, will lead to acrimony "because we will have given the whip hand in all future negotiations to Brussels".

Image source, Reuters

What could happen in Parliament this week?

• Tuesday: MPs return to the Commons after their summer recess. Opposition MPs are expected to put forward legislation to stop a no-deal Brexit under "SO24" or Standing Order 24. This would be the bill's first reading.

• Wednesday: In theory, the bill would then be debated and could potentially pass through all further Commons stages. However, the bill must pass through a series of votes and receive backing from more than half of MPs to pass to the next stage. Boris Johnson's first PMQs as prime minister also takes place.

• Thursday: If MPs passed the bill, it could then reach the House of Lords by Thursday, but consideration of the bill could spill into Monday. It will be debated and voted on. The House is not due to sit on Friday.

• Monday, 9 September: If the bill passes these hurdles it could gain Royal Assent, formally making it law.

The Brexit Party leader Nigel Farage has previously said he would be open to an electoral pact with the Conservative Party - if Boris Johnson were genuine about taking the UK out of the EU on 31 October.

An electoral pact usually involves not fielding candidates in specific areas, in order to allow another party a better chance of winning.

On Sunday Tory minister Michael Gove refused to say whether the government would abide by legislation designed to stop the UK leaving the EU without a deal.

Asked if the government would abide by a law blocking no-deal Brexit, Mr Gove said: "Let's see what the legislation says."

Professor of government Vernon Bogdanor says: "The law applies to the government as much as the rest of us.

"There is no way the government can ignore a law passed by Parliament.

"Boris Johnson has said don't expect me to carry it out - I will take it to the public to decide."

One detail about the prime minister's plan, should he be defeated in the House of Commons over no-deal Brexit, has raised some eyebrows.

If he calls an election, the suggested date is October 14 - a Monday rather than a Thursday.

It's not unprecedented to have an election on a day other than a Thursday, but it is unusual. You have to go back to Tuesday 27 October 1931 to find the last time it happened.