THE Halloween Brexit deadline is fast approaching and yet the UK’s political fate remains unknowable – Deal, No Deal or Delay? All should become clearer after a historic House of Commons showdown today.

What is Super Saturday?

TODAY there will be an extraordinary sitting of Parliament – the first on a weekend since April 1982 – to discuss Boris Johnson’s new Brexit deal.

If MPs do not approve the deal, the Prime Minister faces an almighty clash over whether he will request a further Brexit delay from Brussels as he is compelled to under the Benn Act.

What’s happening today?

THE Commons will sit from 9.30am and the Lords will sit from 10am. The first order of business will be a statement from Johnson to update the House after the EU Council summit. After the PM’s statement, the Government is expected to move its motion seeking approval for a Brexit deal.

MPs have been able to table amendments since Thursday night, and Speaker John Bercow can select as many amendments as he wants, with votes taking place on those before the vote on the Government motion.

The debate on the motion can run until any time on Saturday – there is not a 2.30pm cut-off time.

Will MPs approve the deal?

THE vote could come down to the tightest of margins. DUP MP Sammy Wilson has said his party would continue to hold firm and vote against the deal, while Nicola Sturgeon has ruled out SNP MPs backing the deal. “It’s hard to imagine a deal that could be worse from the perspective of Scotland’s interests,” the First Minister said.

READ MORE: Brexit: 'Hard to imagine' worse deal for Scotland, says Sturgeon

Jeremy Corbyn was quick to dismiss the agreement, and said Labour could not support the deal. But doubt remains about Labour MPs in Leave-voting constituencies. And The Daily Telegraph reported that between 10 and 15 Labour MPs are prepared to back the deal to avoid a No-Deal scenario.

Is it as simple as one yes or no vote?

NO. MPs amended the Saturday sitting motion by approving a proposal tabled by former Tory Sir Oliver Letwin, now an independent.

The National: Sir Oliver Letwin

Letwin explained this would allow MPs to move amendments to the Government’s proposal and for them to be voted on if selected by the Speaker, as mentioned above.

The SNP has tabled an amendment to reject the deal, demanding an immediate extension to the October 31 deadline and a General Election.

Letwin has put forward an amendment that, if accepted and approved, would force the Government to pass the European (Withdrawal Act) Bill before a meaningful vote could be held.

What will happen if the deal passes?

IF the Prime Minister is successful in Westminster, he will then have to hope that MEPs in the European Parliament give it the same backing – a point reiterated by European Commission president Jean-Claude Juncker on Thursday. Attention will also turn to passing the necessary legislation to make the UK’s EU withdrawal legally enforceable.

READ MORE: Angus Robertson: Brexit shows Scotland has been cast aside by Westminster

Johnson would need to find a further majority for the European Union (Withdrawal Agreement) Bill in order to put Brexit on the statute books.

But what if the deal is rejected?

IF Parliament does not support the deal, the Prime Minister is compelled under the Benn Act to request a further Brexit delay until the end of January.

Juncker piled the pressure on MPs to back the deal by raising doubts over any further delay to the UK’s departure beyond the end of the month. But European Council president Donald Tusk said if there is a request for an extension he will “consult with other member states to see how they react”.

How rare is a Saturday sitting THE Commons has only sat on four Saturdays since 1939, including on September 2 that year, due to the outbreak of the Second World War. The last time there was a Saturday sitting was April 3, 1982, following the invasion of the Falkland Islands.

MPs also sat on Saturday, July 30, 1949, to finish up business before summer recess and on Saturday November 3, 1956, due to the Suez crisis.