Theresa May has appealed to Tory rebels not to undermine her negotiating position with the EU by backing amendments to Brexit legislation made by the Lords.
Addressing a meeting of the backbench 1922 committee on Monday ahead of a series of crunch Commons votes, the Prime Minister told MPs to consider the signal that would be sent to Brussels if the Government was defeated.
Mrs May 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.”
The plea came as the EU (Withdrawal) Bill returns to the Commons on Tuesday with ministers seeking to overturn a raft of amendments by the House of Lords intended to keep Britain close to the EU after Brexit.
However, they face a revolt by pro-EU Tory MPs determined to retain as many of the changes as possible in the legislation.
Mrs May made the point to backbenchers that while the Bill itself may be a largely technical measure, the way that they vote in the division lobbies on Tuesday and Wednesday will send an important signal to the country.
“The purpose of the EU Withdrawal Bill is simple – it is putting EU legislation into law to ensure a smooth and orderly transition as we leave.
“But the message we send to the country through our votes this week is important. We must be clear that we are united as a party in our determination to deliver on the decision made by the British people.
“They want us to deliver on Brexit and build a brighter future for Britain as we take back control of our money, our laws and our borders.”
Despite depending on the votes of the 10 DUP MPs for her precarious Commons majority, there were signs of cautious optimism among ministers that they would get the numbers to see off the revolt.
Some pro-EU Tories were reported to be backing away amid fears Mrs May could be fatally damaged by defeat, opening the way for a hardline Brexiteer to take over at the top of the party.
However, ministers were said to be taking nothing for granted with whips continuing to talk to MPs over the weekend – conversations that were expected to continue into the week.
The Government is thought to be most vulnerable on two amendments – one on the customs union and the other giving Parliament a decisive say over what happens next if it rejects a final Brexit deal.
Ahead of the 1922 meeting, Conservative Remain campaigner Sarah Wollaston called for “further concessions” on the customs union.
The Totnes MP said she was “minded” to rebel to support a Lords amendment on giving Parliament a meaningful vote on an exit deal, telling the BBC: “We would like to see further concessions on the amendment on the customs union because it is just a very sensible amendment that says keep it on the table, don’t completely rule it out.”
The votes follow another bruising week for Mrs May over Brexit which saw David Davis reportedly threaten to resign unless there were changes to the Government’s latest “backstop” proposal to avoid a hard border between Northern Ireland and the Republic if there is no overall deal.
It then emerged Boris Johnson had privately suggested Donald Trump would make a better job of the Brexit negotiations than Mrs May was doing while the EU’s chief negotiator, Michel Barnier, rejected key elements of the “backstop” plan.
Mr Davis was in Brussels on Monday for the latest round of negotiations with Mr Barnier.
The Brexit supporter told LBC radio on Monday that he would not expect people like pro-Remain MP Ken Clarke, who have “strong principles”, to change their minds.
Mr Clarke had urged the rebels to hold their nerve, arguing on Sunday that if they succeeded they would strengthen Mrs May’s hand against the Brexit hardliners in the Cabinet.