The usually poker-faced Angela Merkel couldn't contain a chuckle at the G7 in Biarritz on Monday as Trump announced his plans to visit Germany "soon" at the German chancellor's invitation.

In a news conference held prior to their bilateral meeting on the sidelines of the G7 summit, a reporter asked Merkel if she had invited the US president to Berlin, and if so, how he had responded, according to CNN footage.

The German chancellor said she had invited Trump "many times" on previous occasions, and then deferred to the US president.

Trump responded, "We'll be there … we're very honored by the invitation — and that's true — and we will be there. Maybe soon," he said, before adding, "I have German in my blood," at which Merkel raised her eyebrows and chortled.

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When pressed about whether the visit could happen before his trip to Poland at the end of the week, Trump initially said "maybe," but then backtracked and said it might be a bit too short notice.

Trump later tweeted a positive message about his "very productive" meeting with the German chancellor.

In the hours after the news conference, #TrumpNotWelcome began trending on Twitter in Germany, with many Twitter users expressing hostility and lack of interest at the prospect of the US president visiting Germany, and amusement at Merkel's reaction.

Despite several invitations, the US President has never been on a bilateral diplomatic visit to Germany during his time in office. In 2017 he attended the G20 summit in Hamburg, and in late 2018 he paid a surprise visit to the Ramstein Air Base on his way back from Iraq to visit with US armed forces stationed there.

Read more: Why is Donald Trump ignoring Germany?

Germans' confidence in the US president took a nosedive following Trump's election in 2016, according to a 2018 Pew study, with roughly one in 10 Germans expressing confidence in Trump from 2016 to 2018.

Following Trump's announcement of his plans to visit Germany, the mayor of the hometown of Trump's grandparents, Kallstadt, shrugged at the news. "If he comes, then he comes, if he doesn't then he doesn't. Until then, our church clock will keep ticking as usual," Mayor Thomas Jaworek told dpa on Monday.

The mayor of the 1,200-person village in the western German state of Rhineland Palatinate said he wasn't aware of any plans for Trump's visit, but that "as I perceive Donald Trump, he is one for surprises. Maybe he'll be at my front door asking for breakfast tomorrow morning," he continued.

Read more: Donald Trump's German roots

The US ambassador to Germany Richard Grenell told dpa that last year Trump expressed interest in visiting Kallstadt. "I don't know when, but he told me he wants to come and see the hometown of his family," Grenell said in December.

Merkel said she had "no specific date" yet for when Trump could visit Germany.

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