THERESA May faces her toughest challenge yet today as she bids to get her Brexit legislation back to how she wants it.

The EU Withdrawal Bill suffered 15 defeats in the House of Lords last month, and comes back to the Commons this afternoon markedly different.

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Over the next two days, the Prime Minister hopes her MPs will support her efforts to undo all the changes made by the peers. On top of that, she will be asking the Tories to oppose any attempts to further change the bill.

The problem for May is that she doesn’t have a majority in the Commons and, if all the other parties are against her, she needs the support of all of her MPs, and the help of Northern Ireland’s 10 Democratic Unionist Party MPs, to prop her up.

Currently, thanks to a by-election caused by the resignation of a Labour MP, that small working majority has been bumped up to 14.

What might make things a little easier for the Tory boss is that Labour are hopelessly split on some of the big issues too. Though the leadership are telling MPs to vote on all but one of the Lords’ changes.

The two votes likely to be most tricky, will be amendment one, calling on May to negotiate a customs union with the EU, and amendment 19 ,which demands on a “meaningful” vote on the final Brexit deal.

This would guarantee MPs a vote on whatever is agreed by May, David Davis and Brussels.