Ahead of attempting to raise his profile abroad today with a visit to fellow socialist Portuguese Prime Minister Antonio Costa, the Labour leader was in danger of being made an international laughing stock over his attacks on US President Donald Trump.

Mr Corbyn had described Mr Trump as an “abhorrent, dangerous and a threat to our society” for retweeting anti-Islamic messages from far right group Britain First.

But then the Labour leader’s brother Piers, a meteorologist, put out a message: “'PEOPLE! WAKE UP. My Take is #Trump deliberately ReTweeted from someone who he knew would cause offence in order to magnify publicity and expose many politicians in front of the people for attacking the messenger (him) rather than discuss the content of the news concerned.”

He then retweeted Mark Collett, a former leading member of Young BNP, who said: “Theresa May is an utter disgrace. She is an Islamic appeaser, multiculturalist & pawn of the internationalist bankers.”

There was further embarrassment after he was unveiled as the front cover interview of GQ magazine.

The magazine’s editor Dylan Jones said that doing the photoshoot was "as difficult as shooting any Hollywood celebrity".

He appears in a dark Marks & Spencer jacket and red tie, but editor Mr Jones said his entourage initially did not appear to understand that he would have to be "presentable" for the shoot.

The editor revealed that Mr Corbyn had turned down an interview with their regular political writer, Tony Blair's former aide Alastair Campbell.

And he said the interviewer Stuart McGurk had gone into the interview as "something of a fan", but was "quickly disillusioned".

"I think he started to subscribe to the theory - which lots of people do - that Corbyn is a bit of a Wizard of Oz character, that he does appear to be the weaker part of the relationship," said Mr Jones.

"I think that the overriding thing that Stuart came away with was that he's not fantastic on detail ... When he was pressed on who his business advisers were, he couldn't name a single one.

"Also a strange lack of hinterland. He couldn't name a single film that he'd seen in the last year, couldn't name a book that he'd read in the last year. It was kind of strange."

However, he acknowledged that this might reflect the Labour leader's "air of authenticity", saying: "I think it's interesting that perhaps he hadn't been given briefing notes about what it might be best to say.

"He is obviously the most divisive character in Westminster at the moment. But he does have an air of authenticity about him and I think that myopic view that he has is very, very appealing to people."