Donald Trump has deflected questions about allegations GCHQ spied on him, saying he was just repeating somebody else's claims.
Mrs Merkel and Mr Trump appeared to have an awkward meeting at the White House, with the US President seemingly refusing to shake the German Chancellor's hand in front of the media in the Oval Office.
At the start of her visit, she said it was "much better to talk to one another than about one another".
In a joint news conference with German Chancellor Angela Merkel, the US President was asked whether he regretted tweeting the claim that the Obama administration had wiretapped Trump Towers during the election.
In his reply, he made a reference to claims that Mrs Merkel had been the subject of surveillance by Mr Obama in 2010.
1. Merkel's reaction to Trump continuing to lie about wiretapping is 🔥
2. Why are reporters laughing as POTUS lies to them? pic.twitter.com/vcNUREkWGy
— Judd Legum (@JuddLegum) March 17, 2017
He said: "As far as wiretapping, this past administration, at least we have something in common perhaps.
"We said nothing - all we did was quote a certain very talented legal mind who was the one responsible for saying that on television. I didn't make any opinion on it.
"That was a statement made by a very talented lawyer on Fox and so you shouldn't be talking to me, you should be talking to Fox, ok?
Mr Trump was referring to US media commentator Judge Andrew Napolitano, who made the original accusation about GCHQ involvement on Wednesday.
That claim was then repeated by White House press secretary Sean Spicer, who has repeatedly said the US President stands by the allegation and does not regret making it.
On Thursday, US Congress rejected that claim.
Trump expects to do well in German trade deals
Donald Trump also said today that he expects to do fantastically well in trade deals with Germany.
In today's White House news conference with Angela Merkel, the president reaffirmed his support for Nato and praised her efforts to tackle Islamic State militants.
On the election campaign trail, the president had accused the German leader of liberal immigration policies.
The two leaders discussed NATO funding, trade agreements and the international situations in Ukraine and Syria, and Mr Trump denied claims his policies were isolationist.
He said: "I don't believe in isolationist policy, but I also believe that a trade policy should be fair.
"I am a free trader, but I'm also a fair trader."
