Republican presidential candidate Donald Trump speaks at a rally in Anaheim, California | Spencer Platt/Getty Images Donald Trump on Brexit: Huh? The UK’s referendum on EU membership isn’t keeping The Donald up at night.

Brexit might be the most pressing issue in Europe, but it's not registering with Donald Trump.

The presumptive Republican nominee for U.S. president didn't seem to understand what "Brexit" meant — a British exit from the European Union — when Michael Wolff of the Hollywood Reporter probed for his stance.

"Brexit, your position?" Wolff asked.

"Huh?" Trump responded.

"Brexit," Wolff said.

"Hmm," Trump said.

"The Brits leaving the EU," Wolff said.

"Oh yeah, I think they should leave," Trump said.

Wolff wrote in the piece that Trump's "lack of familiarity with one of the most pressing issues in Europe is for him no concern nor liability at all."

Trump on Wednesday announced that he will visit the U.K. on June 24, the day after the referendum. He will officially open a golf course resort in Scotland.

In the same interview, Trump was asked if he sees himself in alignment with far-right European politicians such as France's Marine Le Pen and Italy's Matteo Salvini. Trump said he did not see any similarities and denied ties with Salvini, the leader of the Lega Nord, saying: "I didn't want to meet him."

Trump and Salvini have met. The Italian far-right politician tweeted a picture of the two men at an election rally in Pennsylvania on April 25. The meeting reportedly lasted 20 minutes, with Trump allegedly telling Salvini: “I hope you become prime minister of Italy soon.