LIVE: Theresa May battles through final hours to fight off historic Brexit deal defeat

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• LIVE: MPs prepare to vote on Theresa May's Brexit deal.
• The House of Commons will vote on the Brexit Withdrawal Agreement at some point after 7pm this evening, five weeks after it was postponed.
• The prime minister is set for a big defeat, potentially by a majority of over 200 votes.
• The biggest ever defeat on a UK government was by a majority of 166 votes nearly 100 years ago.
• A series of amendments could help to lessen the scale of defeat.
• Jeremy Corbyn is preparing to launch a vote of no confidence in the government.

LONDON - Members of Parliament will tonight vote on Theresa May's Brexit deal after weeks of debate and delay.

MPs will finally vote on the Brexit Withdrawal Agreement on Tuesday evening after the prime minister postponed the so-called meaningful vote last month amid fears of a huge defeat.

Despite assurances from May and the European Union on the most controversial aspects of the deal, specifically the Northern Irish backstop, MPs are set to inflict a big defeat on the deal, according to the latest forecasts.

Sky predicts a majority of 225 MPs will vote against the deal, which would be heaviest defeat for a UK government. The biggest ever defeat was almost a century ago when Ramsay MacDonald's government was defeated by 166 votes.

If, or when, May's deal falls the big question will be what the prime minister will do next.

She is expected to make a statement immediately following the result in which she could spell out a plan B. Jeremy Corbyn's Labour Party is also poised to table a motion of no confidence in the government as early as this evening if the deal is voted down by a huge margin, according to multiple reports.

MPs are set to vote on amendments to the Withdrawal Agreement shortly after 19:00 (GMT) with the main vote coming afterwards and a final result expected later in the evening.

Scroll down for the latest developments in a historic day in British politics. All times are in GMT.

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