An unrepentant Donald Trump lashed out at US spy agencies in his first press conference as president-elect, accusing them of allowing the leak of claims that Russia sought to compromise him and likening the behaviour to “something that Nazi Germany would have done”.

Mr Trump angrily denied the allegations contained in a leaked dossier containing lurid but unverified claims about his personal conduct and his team’s ties to Moscow. The allegations were “fake news” and the product of “sick people”, he said.

Mr Trump told reporters at his New York headquarters that it would be a “tremendous blot” on the reputation of US intelligence community if it had allowed a leak. “A thing like that should never have been written,” he said. “It is all fake news, it is phoney stuff, it didn’t happen.”