Britain seems determined to remain on friendly terms with the United States; on Wednesday, Queen Elizabeth II invited President Trump for a state visit, and Trump accepted.

But that was yesterday.

On Thursday, Trump tweeted his apparent belief that Britain “helped the Obama administration spy on his 2016 presidential campaign,” reports the Washington Post.

“WOW!” the president wrote, predicting it’s “a question of time before the truth comes out…”

“Trump cited a report, attributed to the conservative One America News Network, that cited an accusation of British spying made by Larry Johnson, a former CIA analyst and blogger who has spurred controversies over other false claims as well,” the Post says.

The spying claim has been strongly denied by both U.S. and British officials, and on Thursday a British intelligence spokesman called it “nonsense.”

Two years ago, “Fox News commentator Andrew Napolitano raised the prospect of British spying on air, and Johnson later acknowledged being a source for Napolitano,” the Post says, adding that then-White House press secretary Sean Spicer mentioned the claim. during a press briefing.

“The White House subsequently backed away from the claim, and Fox News disavowed it,” says the Post.

Now, Trump appears ready to revive the controversy, though his motives are unclear. He’s due to visit Britain and meet the queen in early June.