(CNN) President-elect Donald Trump said Thursday he has selected New York Jets' owner Woody Johnson, one of the top fundraisers of his presidential campaign, to serve as US ambassador to the United Kingdom.

Trump announced during a luncheon with supporters in Washington, DC, that Johnson is "going to St. James," an apparent reference to the Court of St. James's. The US ambassador to the UK is known formally as the ambassador to the Court of St. James.

"Congratulations," Trump told Johnson as he pointed out notable members of the audience.

Incoming White House Press Secretary Sean Spicer confirmed Johnson's appointment.

Johnson was rumored for some time to be the top pick for the plum ambassadorship to the UK, one of the US's foremost allies.

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