Article 50 is actually reversible, author of the Brexit treaty clause says

Lord Kerr ridiculed the Government's claims

The author of Article 50 has ridiculed the Government’s claim that the treaty clause cannot be stopped after it is triggered.

Lord Kerr urged the House of Lords to amend the Brexit Bill, launching a fierce attack on the “Bullingdon Boys” who have left others to suffer the pain of EU withdrawal.

He warned that Britain’s economy would be hit by leaving the EU, telling the House of Lords: “There will be a price to be paid.”

“It’s a sad fact that it won’t be those who got us into this fix who will suffer – the Bullingdon boys will be just fine, the country may not be,” the Crossbencher peer said.

At the weekend, Justice Secretary Elizabeth Truss sparked criticism by suggesting Article 50 cannot be revoked while Downing Street has insisted the argument is irrelevant.

But Lord Kerr said: “If, having looked into abyss, we changed our minds about withdrawal, we certainly could - and no-one in Brussels could stop us.”

The peer is one of a number of people who has claimed authorship of the clause. He was Ambassador and UK Permanent Representative to the European Communities and European Union in the 1990s.

Theresa May has been criticised for offering a ‘take-it-or-leave-it choice’, insisting she will crash Britain out of the EU if Parliament rejects the deal she has struck.

But Lord Kerr urged the Lords to reject this “Hobson’s Choice”, calling for the Bill to be amended to ensure the Prime Minister could be told to “go back and try harder”.

He said: “The Government has given us no undertaking that they will come back to Parliament if the negotiations threaten to break down. I rate the chances of breakdown at well over 30 per cent.”

And he added: “No deal is much the worse deal….a disaster for business and citizens alike

“If the bravado of the white paper proves hollow, the Government must come back to Parliament before the clock runs out.”

On the two-year timetable, once Article 50 is triggered, Lord Kerr said: “The European union is a union of democracies. If this Parliament asked – and our Government conveyed our request – for an extension, in my judgement it would certainly be given.”

Peers debated Article 50 late into the night (House of Lords)

The country should be braced for a “more difficult” economic relationship with the rest of the world after Brexit, because Britain would be less advantageous to those countries

“Why should they be so keen to open their markets to us if we are no longer their entry point to a market of 500m. It’s a fact that trade halves as distance doubles.

“The Government knows all these facts, but has decided to put sovereignty ahead of economic wellbeing,” the peer said.

And, in a reference to the notorious Leave campaign, Lord Kerr said: “The country does not know where it is going.

“We are on this bus heading for Heathrow – mendacious slogans on the side – and we have no idea what the destination is.”

He made the comments in the second day of the House of Lords’ debate on the Brexit Bill.