Barack Obama is making what will be his last trip to the UK as president of the United States and has managed to anger politicians backing Brexit.
Obama is very much in favour of the UK remaining in the EU and has spoken up consistently on the matter. Some politicians, London Mayor Boris Johnson among them, feel it's not the president's place to try and influence the vote.
Writing for The Sun and recycling "false" claims about the removal of a bust of Winston Churchill from the Oval Office when Obama became president, Johnson said: "Some said it was a snub to Britain. Some said it was a symbol of the part-Kenyan President's ancestral dislike of the British empire - of which Churchill had been such a fervent defender."
Critics accused him of making a "loaded" attack by referring to the president's ancestry, with Labour frontbencher Diane Abbott claiming Johnson's "offensive" comments echoed those of the "Tea Party" right-wing tendency in the US.
The mayor continued by arguing that Obama and the US would never agree to the kind of arrangements the UK has as a member of the EU.
"It is deeply anti-democratic - and much as I admire the United States, and much as I respect the president, I believe he must admit that his country would not dream of embroiling itself in anything of the kind," he said.
"It is incoherent. It is inconsistent, and yes, it is downright hypocritical. The Americans would never contemplate anything like the EU, for themselves or for their neighbours in their own hemisphere. Why should they think it right for us?"
Asked how David Cameron viewed Johnson's comments on the president's "half-Kenyan" heritage, the Prime Minister's official spokeswoman said: "It is important to engage with the facts.
"If you look at the issue the mayor of London was talking about, which related to the bust of Churchill in the Oval Office, they have been clear that this suggestion that he asked for it to be moved and that it is a failure of the president's appreciation of the special relationship is false.
"That decision had already been taken before president Obama took office, so let's focus on the facts."
Former Labour spin doctor Alastair Campbell went so far as to call the mayor "racist".
Shadow chancellor John McDonnell was another to accuse Johnson of racism.
And MP for Streatham Chuka Umunna likened Johnson's smear of the president to Zac Goldsmith's campaign for London mayor.
While even Winston Churchill's grandson, Tory MP Sir Nicholas Soames, called the article "appalling".
But, never one to sense the mood, Ukip leader Nigel Farage echoed the Mayor's comments: "His first day in the White House, he had the bust of Winston Churchill removed from the Oval Office.
"Because of his grandfather and Kenya and colonialisation, I think Obama has a bit of a grudge against this country."
Well that settles it then.