Brexit march London - live: People's Vote protesters cheer as MPs force Boris Johnson to ask EU for extension

Good morning and welcome to our politics liveblog on the day of a crucial House of Commons vote which is set to decide whether or not the UK leaves the EU on 31 October.

Boris Johnson says ‘get Brexit done’

Boris Johnson has appealed to MPs to back his agreement with Brussels to “get Brexit done” - the phrase he has used repeatedly since he replaced Theresa May as prime minister.

Writing in The Sun, Johnson said: “Today can be the day we get?Brexit?done. There have been any number of false dawns. Deadlines for our departure have come and gone.

“I ask everyone to cast their mind forward to the end of today - and imagine?what it could be like if the new?Brexit?deal has been approved.

“In less than two weeks, on October 31, we would be out of the EU.?“A difficult, divisive and - yes - painful chapter in our history would be at an end.”

Johnson told the BBC on Friday night there is “no better outcome” than his deal.

“I just kind of invite everybody to imagine what it could be like tomorrow [Saturday] evening, if we have settled this, and we have respected the will of the people, because we will then have a chance to move on.

“I hope that people will think well, you know, what's the balance, what do our constituents really want?”

What happens in the Commons on ‘super’ Saturday?

However it is not as simple as a vote for or against the deal, on what is the first Saturday sitting of the Commons in 37 years.

Proceedings are expected to get underway at 9.30am – with Boris Johnson making a statement – but the vote may be delayed into the early evening by a series of proposed amendments: most notably the crucial “Letwin Amendment”.

An uphill battle has been made more arduous by Sir Oliver?Letwin, the former Tory Cabinet minister who now sits as an independent, whose motion allowing for amendments to the Government's proposals was narrowly passed.

The MP subsequently put forward an amendment that, if selected by Speaker John Bercow and approved by MPs, would withhold approval of the deal unless and until implementing legislation has passed.

Sir Oliver explained his move, stating: "In short, my aim is to ensure that Boris's deal succeeds, but that we have an insurance policy which prevents the UK from crashing out on 31 October by mistake if something goes wrong during the passage of the implementing legislation."

Here is our full explainer on the day ahead.

Are you going on the march for a Final Say vote?

Hundreds of thousands of people are expected?to swamp central London to demand a Final Say referendum on the deal.

It could be one of the largest political protests Britain has ever seen, reports political editor Andrew Woodcock.

TUC boss urges MPs to vote against deal

Frances O’Grady, general secretary of the Trades Union Congress, called on MPs to vote against Boris Johnson’s deal.

In a series of tweets, she posted: “It seems govt will today announce these proposals, claiming they’ll protect workers' rights. We've looked at them and this is our analysis. These are paper promises that fail to mitigate the damage that this deal would do to working people.

“These proposals are entirely based on process rather than substance. A rehash of the flimsy offer Theresa May’s govt made in March. They do nothing to protect or improve workers’ rights, now or in the future.”

Bank of England governor says prospect of a deal ‘good news’

Bank of England governor Mark?Carney?said Britain’s planned Brexit deal would help the country's economy, but “almost existential” worries about global trade wars might prevent the BoE from raising interest rates.

Carney?said the deal was “good news” because it means Britain could avoid what the BoE has warned would be a major economic shock: dropping out of the EU with no transition.

In an interview with Bloomberg Television at a meeting of the International Monetary Fund,?Carney?said clarity on Brexit would help to revive business investment that has fallen sharply since the 2016 referendum.

In a separate interview with the BBC,?Carney?said the deal “takes away the tail risk of a disorderly Brexit”.

He said it might not help the economy to the same extent as his predecessor Theresa May’s plan, which proposed closer ties with the EU but was rejected by parliament.

Asked if securing a Brexit transition meant the BoE would resume raising rates,?Carney?said: “Not necessarily. I’m not going to pre-commit, there is a lot of contingencies there.”

Bank of England governor Mark Carney (AFP)?

Steve Barclay refuses to rule out pulling big vote on Brexit deal

Brexit secretary Steve Barclay repeatedly failed to rule out pulling the vote if a rebel amendment to delay Brexit succeeds.

The prime minister’s plans could be thrown into disarray by an amendment from Sir Oliver Letwin, which would withhold MPs approval until all the legislation for the Brexit deal has been passed.

This would mean the PM has to seek a delay from Brussels, after MPs passed a law compelling him to seek an extension if he had not struck a deal by 19 October.

Asked if the vote would go ahead, Mr Barclay said: “It’s always for business managers and we are focused on winning the deal, the vote and not having the Letwin amendment.”

Pressed again, he said: “We will address that if that vote passes.

Asked if it might not pass, he said: “But we are committed to defeating that because it will add further delay, further dither, further uncertainty, which is bad for investment and the economy.”

Brexit: What does Super Saturday have in store?

Could the government be ready to pull Brexit deal vote?

Speculation that No 10 is set to pull the big vote on Boris Johnson’s Brexit deal, if the Letwin amendment passes.

BREAKING: Speaker John Bercow selects Letwin amendment

Sir Oliver Letwin’s amendment has been selected for a vote. If it passes it looks as though the government will pull the big vote on its Brexit deal.

According to the BBC’s Laura Kuenssberg it could be put back until Tuesday.