AFTER a year and a half of wrangling, Tory in-fighting and delays, tomorrow will finally bring the so-called meaningful vote on Theresa May’s Brexit deal.

The ballot was supposed to be held on December 11 but was delayed when the Prime Minister realised she was facing an embarrassing defeat, partly due to rebellion in her own party.

May was originally vague about when the vote would be rescheduled for and eventually caved into pressure.

Some MPs insisted that the debate be held before Parliament broke up for Christmas but those calls fell on deaf ears.

The Prime Minister eventually announced that the vote would take place this week, with MPs given another week to debate the plan from January 7.

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But what is the meaningful vote, when will it take place and what are the likely scenarios? Here is everything you need to know.

What is the meaningful vote?

The meaningful vote is a chance for MPs to have their say on May’s Brexit deal and what the future relationship between the UK and the EU will look like. Under Section 13(1) of the European Union (Withdrawal) Act 2018, it is required that the Withdrawal Agreement is put to MPs in the House of Commons as well as to the House of Lords.

When will the vote take place?

The exact timing of the vote is still to be confirmed though it is expected to take place sometime between 7pm and 9pm tomorrow. Ministers have been debating the deal since last Monday.

What is the likely outcome?

Just as was the case last month, May looks likely to lose the vote. Not only will many opposition MPs vote down the deal, somewhere in the region of 100 Tory MPs are expected to vote against their leader.

As well as this, the DUP, who are propping up May’s minority government, are expected to oppose the deal.

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It means that May will be hoping that enough opposition MPs break party ranks and vote in favour of the deal.

But with the SNP MPs all expected to vote against the deal, expecting upwards of 100 Labour MPs to go against their own leadership – which opposes the deal – seems unlikely.

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May’s best hope appears to be a narrow defeat, allowing her to return to the EU to renegotiate. A heavy defeat, however, would leave the Prime Minister vulnerable to a no confidence motion in her government.

Even if May were to return to Brussels for further negotiations, the EU is unwilling to budge on the Irish backstop, the main contention of Brexiteers.

The Prime Minister has been trying recently to gain further concessions from the EU, and is due to make a speech this afternoon.

However, a letter from European Commission President Jean-Claude Juncker and President of the European Council Donald Tusk said that the EU is refusing to renegotiate the Withdrawal Agreement but clarified that the backstop is “intended to apply only temporarily, unless and until it is superseded by a subsequent agreement".

What happens if the deal passes?
If MPs vote in favour of May’s deal it will then be given to the Lords who will likely also vote in favour. However, the chances of this scenario coming to pass are unlikely.

What happens if the deal doesn’t pass?
This is the most likely scenario. If this happens, Labour will try to force a General Election by calling a motion of no confidence in the Government.