Tory peer and former deputy prime minister Lord Heseltine has warned the House of Lords against waging a long-running battle to make changes to the Article 50 Bill.
The unelected chamber installed two amendments to the legislation, on protections for the rights of EU nationals, and offering parliament a “meaningful” vote on any new trading relationship with the EU.
The latter could see MPs force Theresa May back to the negotiating table if they do not approve any new deal.
MPs will consider the changes tomorrow, but despite backing one of the changes, Heseltine said peers should be prepared to back down.
“I have made a point of not trying to advise Members of Parliament what they should do. It’s entirely for them. What is the proper responsibility of the House of Lords is to give them the opportunity to express a view. That we have done, and we shall see what they do,” the Tory peer said on Peston on Sunday.
Asked what should happen if MPs reject the amendments, Heseltine added: “I told the chief whip a week ago that if that were to happen, and I would not be surprised if it were to happen, then the arguments for the supremacy of the Commons would be very powerful.”
Heseltine also blasted foreign secretary Boris Johnson over Brexit, accusing the Tory frontbencher of “waffle, charm and delay” in a bid to dodge questions.
Heseltine slapped down Johnson over a cross-party report which had warned against a lack of planning against quitting the EU without a trade deal.
The foreign secretary said the UK would be “perfectly okay” without agreeing trade terms with European member states.
“As it happens, I think we would be perfectly okay if we weren't able to get an agreement, but I'm sure that we will,” Johnson said.
But Heseltine blasted Johnson's comments as “rubbish”.
“When I listen to Boris, who I like actually, he took over from me in Henley, he has turned the art of political communication into a science in which waffle, charm, delay, anything to stop actually answering questions,” the Tory peer said.