JOHN Bercow has branded Brexit the “biggest foreign policy mistake in the post-war period".

The former Speaker, who last week stood down from his role at Westminster after 10 years, told a group of foreign journalists in London that while he was impartial in chairing proceedings in the Commons chamber, he could now express an opinion.

In a recording of the event by the Turkish Anadolu Agency, Mr Bercow said: "I'm no longer the Speaker, I don't have to remain impartial now and if you asked me honestly, do I think that Brexit is good for our global standing? The honest answer is no, I don't.

“Brexit is the biggest foreign policy mistake in the post-war period and that is my honest view."

Mr Bercow angered many pro-Brexit MPs for what they claimed was his bias to thwart Britain’s exit from the EU.

Earlier, he explained: "The honest answer is that I don't think it helps the UK. Let me say for the umpteenth time, for the avoidance of doubt, that I believe I was always fair in the Chair.

"Fair to the Brexiteers, to whom I granted urgent questions and emergency debates before the word 'Brexiteer' had even been invented.

"For years, Bill Cash, Bernard Jenkin, John Redwood, John Baron, all of them know that I selected an amendment to the Queen's Speech in 2013 calling for a referendum on British membership of the EU.

"Why did I select that amendment? Because it was heavily signed and I thought it was a legitimate proposition which should be put to the House of Commons and the House of Commons rejected it.

"Some people have said it was part of a sequence of events that caused David Cameron ultimately to change his mind and to decide to have a referendum. Well, that's a matter for him, that's not a matter for me.

"But what I'm saying is I always treated the Brexiteers in a fair way and I've always treated the Remainers in a fair way. And I will assert to anybody that will listen until my dying day that I have been impartial in the chair, pro-Parliament and impartial in the chair," said the former Conservative MP.

He added: "I completely respect the right of the Prime Minister, leading the largest party in Parliament, to try to get support for his position, which is to get Brexit done.

"If he had the numbers, he could have got the first phase done and he made a start be getting agreement towards the end, but not to the legislation, so he decided to leave that and instead to seek a public mandate.

"I respect his right to his view which is a view very widely shared but there is an alternative view equally that is very widely shared and my own personal opinion is that Brexit does not help us.

"We are part of a world of power blocs and trade blocs and my view is that it is better to be part of that power bloc and of that trade bloc than not."