Brexit woes for PM as she warns against undermining talks
Theresa May is less likely to face defeat on the customs union vote.
Theresa May is facing 48 hours of parliamentary warfare as the Prime Minister battles to get her Brexit legislation back on track.
Mrs May appeared to have defused a potentially explosive row over the EU customs union as Tory pro-Europe rebels and Brexiteers came together to table a compromise amendment.
However, the Government remained vulnerable to a humiliating defeat on giving Parliament a decisive say over what happens next if it rejects a final Brexit deal as the EU (Withdrawal) Bill returns to the Commons on Tuesday and Wednesday for crunch votes.
Mrs May set the tone for a tense two days as she warned Tory Remainers that if they defied her and backed Lords amendments to the landmark Brexit legislation it would weaken Britain's hand at the negotiating table.
In what was seen at Westminster as a boost for the Government, a potential defeat for Mrs May on the customs union seemed less likely as a compromise amendment was put together by Remain backers Sir Oliver Letwin and Nicky Morgan, as well as Brexiteers Jacob Rees-Mogg and Sir Bill Cash, which called for "a customs arrangement" with the EU.
Sir Bill told the Press Association it represented a "holding position" and was "flexible" enough for him to support.
Government sources signalled to the Press Association that ministers were set to back the move.
However, the compromise is only likely to delay a full-blown showdown on the customs union until trade legislation returns to the Commons in July.
Addressing a meeting of the backbench 1922 Committee on Monday, ahead of the key votes, the Prime Minister said: "We must think about the message Parliament will send to the European Union this week.
"I am trying to negotiate the best deal for Britain. I am confident I can get a deal that allows us to strike our own trade deals while having a border with the EU which is as frictionless as possible.
"But if the Lords amendments are allowed to stand, that negotiating position will be undermined."
Following Mrs May's address to Tory MPs, Solicitor General Robert Buckland appealed for unity, saying: "There's ongoing work happening and I think it's emblematic, actually, of a real sense of common purpose in the party that we all hang together or we all hang separately."
Writing in The Guardian, shadow Brexit secretary Sir Keir Starmer said: "Instead of negotiating for Britain, the Prime Minister is lurching from crisis to crisis, increasing the risk that the talks break down, and we crash out without an agreement. We cannot go on like this."
Sir Keir said a Government compromise on a meaningful vote for Parliament at the end of the Brexit process would instead turn it into a "meaningless vote" if backed by MPs.
Tory former attorney general and leading pro-Europe rebel Dominic Grieve urged ministers to back his compromise amendment on the meaningful vote.
Meanwhile, Ireland's premier raised the possibility of delaying Brexit to allow more time to negotiate the UK's exit deal.
Taoiseach Leo Varadkar said extending the March 29 2019 departure date was one of a number of "different scenarios" that could be pursed if a withdrawal agreement fails to materialise in the coming months.