American news journalists are praising German reporters for holding Donald Trump's feet to the fire over his unsubstantiated wiretapping claims.

Deutsche Presse-Agentur reporter Kristina Dunz's robust questioning of the President during a joint press conference with Chancellor Angela Merkel led Mr Trump to respond: "Nice, friendly reporter."

Mr Trump has come under increasing pressure over his sensational claim, made on Twitter, that former President Barack Obama had Trump Tower under surveillance around the time of the election last year.

On Thursday the Senate Intelligence Committee said it had "no indications" that was the case.

Ms Dunz asked, according to a translator: "Why are you so scared of diversity in the news, and in the media, that you speak so often of fake news? And that things after all, in the end, cannot be proven, for example, the fact that you have been wiretapped by Mr Obama?"

Mr Trump's answer largely addressed her other question, regarding his global trade policy, however, and he rejected the suggestion he was an "isolationist".

A second reporter asked the President what his response was to GCHQ's rejection of claims made on Fox News, repeated on Thursday by White House press secretary Sean Spicer, that it was behind the alleged wiretap.

Mr Trump said: "We said nothing. All we did was quote a certain, very talented legal mind, who was the one responsible for saying that on television. You shouldn't be talking to me, you should be talking to Fox."

Senior US journalists queued up to praise their German counterparts.

Clara Jeffery, the editor in chief of Mother Jones, said they were getting "far better reviews than the US press corps", while Philip Ricker, the Washington Post's White House bureau chief, added: "Good for German reporters, asking Trump tough and direct questions on wiretapping."