Downing Street denies it will back down over fixing date of Brexit

British prime minister, Theresa May
‘As the PM has said, we want to listen to parliament,’ the prime minister’s spokesman said. Photograph: Virginia Mayo/AP

Downing Street has slapped down suggestions that the government is preparing to drop its attempt to fix the date of Brexit as 29 March 2019, despite the serious prospect of losing a vote on the issue in the Commons.

David Lidington, the justice secretary, had suggested on Thursday that the prime minister was open to listening to suggestions from rebel Conservative MPs who are concerned enshrining the exit date in law could tie the UK’s hands in negotiations with Brussels.

And on Friday a cross-bench committee of MPs sharply criticised the plan, warning that such a tactic would backfire.

However, No 10 said it was not considering backing down over its unexpected amendment to the EU withdrawal bill that sets the point of Brexit at 11pm on 29 March 2019.

“As the PM has said, we want to listen to parliament,” the prime minister’s spokesman said. “We are clear, though, on our determination to get the best possible outcome for the UK. Key to doing that is certainty.

“What the amendment does is provide certainty over our position that we are leaving the EU on 29 March 2019. We would encourage all MPs to support it.”

Later on Friday the Brexit select committee, made up of a majority of Tory MPs, said that stipulating the exact moment of departure would dangerously tie the hands of ministers and hamper their ability to extract the best deal during last-minute haggling.

“We need to maintain flexibility as the negotiations proceed,” said the committee chairman, Hilary Benn. “But ministers are now proposing to remove from the [withdrawal] bill the power to set different exit days for different purposes and replace it with a single exit day. This would create significant difficulties if the negotiations were to continue until the 59th minute of the 11th hour, as the secretary of state suggested to us might happen.”

Last week the Brexit secretary, David Davis, first proposed the new clause, stipulating departure at precisely 11pm on 19 March, amid mounting anxiety among Tory backbenchers that the government was preparing a series of concessions to the EU.

But the symbolic move appeared to have instead galvanised a rebellion among moderate Tories worried that ministers were taking an overly dogmatic approach. Half the Tories on the committee voted with its Labour chairman and other parties in calling for a rethink.
“The flexibility to set multiple exit days was described to us as a tool for setting different commencement dates for different provisions and providing for possible transitional arrangements,” says the committee report. “The government’s latest amendments will however, if agreed by the House, remove this flexibility.”

Lidington had previously hinted the government was considering softening its stance, when he spoke at a lunch for journalists in the House of Commons.

Asked whether the exit date amendment could be withdrawn, he said: “It’s hypothetical but as the PM said, various constructive suggestions have been made during the committee debates about how the bill might be improved and obviously we will listen to ideas coming from colleagues across the house during the bill’s progress in both the Commons and Lords.

“All that clause was designed to do was clarify and put beyond doubt what is already inherent in the wording of article 50. Article 50 says that after two years of the date of notification unless there is a withdrawal the treaties cease to apply to the country that is leaving.”

Speaking later in London, May’s deputy spokesman said the amendment was seen as necessary even though the timing of the triggering of article 50 on 29 March this year started a formal two-year countdown to exactly the same date.

“We think it provides important certainty,” he said. “We have listened to the views of members from all sides of he house and we think the amendment does provide important certainty on this issue.”

Asked what legal difference the amendment would make, he said: “It’s the issue of certainty is what’s key.”

Conservative rebels are confident the government would almost certainly lose if it put the amendment to a vote, since more than 15 MPs are prepared to defy the whip, but most believe that will be averted by a compromise by No 10.