BORIS Johnson has plunged the UK's Brexit negotiations into controversy after he compared French President Francois Hollande to a World War Two camp guard administering "punishment beatings".

The Foreign Secretary's comments were widely condemned.

Guy Verhofstadt, the European Parliament’s chief Brexit negotiator, said they were “abhorrent” and called on Theresa May to denounce them.

Jeremy Corbyn’s spokesman branded them “wild and inappropriate” while Tim Farron, the Liberal Democrat leader, described them as “utterly crass”.

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Ed Miliband, the former Labour leader, tweeted: “Boris Johnson proves once again he's not fit to be Foreign Secretary. Showing you can be supremely clever and yet immensely stupid.”

During a visit to India, Mr Johnson responded to comments from an aide to Mr Hollande, who had said Britain should not expect a better trading relationship from outside the EU.

Warning the EU against adopting a punitive approach to the Brexit talks, the Secretary of State said: "If Monsieur Hollande wants to administer punishment beatings to anyone who chooses to escape, rather in the manner of some World War Two movie, then I don't think that's the way forward. It's not in the interests of our friends or our partners."

No 10 sought to play down Mr Johnson’s comments, dismissing “hyped-up” media reports, and saying the Foreign Secretary was merely making a “theatrical comparison”.

Brushing aside suggestions he should apologise, the PM's spokeswoman said she was not aware of any complaint from the Elysee Palace.

"He was making a point. He was in no way suggesting that anyone was a Nazi," she declared.

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Asked whether or not it would be better for Government ministers to avoid wartime comparisons as the UK enters sensitive negotiations with its European neighbours, the spokeswoman said: "There is not a Government policy of not mentioning the war."

She insisted the Foreign Secretary was not a liability and the Prime Minister retained full confidence in him.

Mr Johnson’s comments came just 24 hours after Mrs May warned her Cabinet colleagues about keeping their discipline and avoiding using a “stray word,” that could make the Brexit negotiations more difficult.

In other developments:

*The PM will today deliver a keynote speech at the World Economic Forum in Davos, Switzerland, and will have meetings with business leaders and bilaterals with other national leaders;

*the UK Supreme Court said the judges would deliver their ruling on the Brexit case - as to whether or not MPs and MSPs should have a vote on the UK Government’s strategy - next Tuesday;

*Sadiq Khan, the London Mayor, speaking in Davos, warned a hard Brexit could “rip Britain apart”;

Read more: David Mundell dismisses SNP Brexit plan ahead of Whitehall showdown

*Mr Corbyn in a Labour political broadcast last night accused the Tories of prioritising “tax giveaways to the wealthiest and big business rather than funding our health service”;

*Donald Tusk, the European Council President, described the PM’s Brexit stance as closer to that of Sir Winston Churchill than US President-elect Donald Trump;

*the Equality and Human Rights Commission warned a new surge in hate crime could be sparked when Article 50 is triggered;

*Brandon Lewis, the Policing Minister, said the UK Government was not ruling anything in or out over its future arrangements with Europol, saying it would be looking to develop a "unique and bespoke position" and

*Brexit Secretary David Davis admitted he made £1,000 by betting on a vote for Brexit.