Brexit: 'The time is now' for Britons to change mind on leaving EU, says Tory MP and former Attorney General Dominic Grieve

Exclusive: Former cabinet minister warns the next six months are 'decision time' over UK's withdrawal from EU

Dominic Grieve said MPs 'should not exclude the possibility that people’s opinion may change' (Rex)

Dominic Grieve has warned the public it is running out of time to change its mind on Brexit, saying the next few months are “decision time”.

The former Attorney General told The Independent it would soon be too late to reverse the decision to leave the EU, and urged people to make their minds up in the next six months.

“The six months we have between now and the autumn are so important,” he said. “It is going to be decision time. And decision time in the sense of what happens in the next six months being a final decision.

“If people do want to change their mind, and they could if they wanted to, the time is now. It cannot be after 29 March 2019, and frankly it cannot be after the end of the autumn of this year.”

While he did not endorse calls for a second EU referendum, Mr Grieve said it was important to give people the chance to change their minds on Brexit.

“I’m not calling for a second referendum,” he said. “But we should not exclude the possibility that people’s opinion may change. And to start from an opinion on an issue that was expressed 18 months ago, where people are bound to have had their opinion influenced since, we must be very careful to listen about what it is they want.”

He continued: “It the most extraordinary conundrum. We have an instruction from the electorate, by a small but significant majority, to do something that many of us [in Parliament] think is going to be very hard to achieve without serious damage to the wellbeing of every citizen in this country. It is an ethical conundrum and it is a practical conundrum.”

Mr Grieve, who served as Attorney General under David Cameron, has been a vocal critic of the Government’s Brexit stance. It was his parliamentary amendment that forced the Government to give MPs a binding vote on the final Brexit deal, leading to him being called a “traitor” and “mutineer” by right-wing newspapers.

His latest warning comes ahead of a pivotal week for Theresa May as she attempts to find common ground between her warring cabinet ministers over Britain’s future relationship with the EU.

Ministers are gearing up for a major battle as senior Conservative figures prepare to meet to thrash out the Government’s position on the single market and customs union.

Remainers Philip Hammond, the Chancellor, Amber Rudd, the Home Secretary, and Greg Clark, the Business Secretary, have suggested the UK should maintain a customs union with the EU.

They were joined by backbench Tory rebels Anna Soubry and Ken Clarke, who said they would try to build cross-party support for maintaining the existing relationship.

However, opponents say a customs arrangement with the EU would stop Britain making new trade deals after Brexit.

Brexiteers Boris Johnson, the Foreign Secretary, Liam Fox, the International Trade Secretary, and Michael Gove, the Environment Secretary, are set to use two crunch meetings of the Cabinet’s Brexit sub-committee next week to insist that Britain leaves the customs union.

It places them on a collision course with the Prime Minister, who is reported to be considering plans for the UK to remain in some form of customs arrangement with the EU.

Downing Street has said the Prime Minister is keeping an “open mind” on the issue.

Mr Johnson, Mr Fox and Mr Gove were backed by leading Brexiteer Jacob Rees-Mogg, who chairs the influential European Research Group of pro-Brexit Tory MPs.

He told BBC’s Today programme: “We need to be free to do deals with the rest of the world.

“We must be out of the protectionist common external tariff which mainly protects inefficient EU industries at the cost to British consumers.”