Donald Trump and his populist advisers in the White House are one of the main three existential threats facing the European Union – and not Brexit - the chief Brexit negotiator of the European Parliament has claimed.

Guy Verhofstadt, a former Belgian prime minister and arch European federalist who recently returned from a tour of the US, said that it was now clear that Europe had “fewer friends than ever” in Washington.

Setting out the three main existential crises threatening Europe, Mr Verhofstad listed radical Islamic terror, the revanchist Russian president Vladimir Putin and his funding anti-EU, far-Right parties and destabilizing Europe and Donald Trump, the new US president.

“We have a third front undermining the European Union, and it is Donald trump who has joined [the far-Right parties] from across the Atlantic. He has talked fairly favourably of other countries wanting to break away from the EU, and that he hoped for disintegration from European Union.”

Mr Verhofstadt singled out the ”enormous influence” of Steve Bannon, the Breitbart News founder who is now chief strategist to Mr Trump and was recently promoted to enhanced positions in the US National Security Council.