His companies have partnered with firms linked to Trump on new digital-currency projects including Dominari Holdings, where his sons sit on the board of advisers and which is based in Trump Tower.

The host of 60 Minutes, Norah O'Donnell, asked Trump why he pardoned Zhao even though government prosecutors had said he caused "significant harm to US national security."

"Okay, are you ready? I don't know who he is", the president said.

Trump added that he did not recall meeting Zhao and had "no idea who he is", only that he had been told that the businessman was a victim of a "witch hunt" by the administration of former US president Joe Biden.

During the interview, Trump also discussed his support for cryptocurrencies and said that the US had to make sure it was a leader in the industry or risk China and its rivals gaining an advantage in the emerging technology.

CBS News is the BBC's US news partner.

The president's pardon lifts restrictions that had stopped Zhao from running financial ventures, but it is unclear whether it changes his standing with US regulators or his role at Binance.

At the time of the pardon, White House Press Secretary Karoline Leavitt called Zhao's prosecution under the Biden administration part of a "war on cryptocurrency", pushing back on critics who said the pardon appeared motivated by Trump's personal financial interests.

"This was an overly prosecuted case by the Biden administration," she said, adding that the case had been "thoroughly reviewed". "So the president wants to correct this overreach of the Biden administration's misjustice and he exercised his constitutional authority to do so."

The Binance platform remains the most used crypto exchange in the world for trading digital assets.

The Trump administration previously halted a fraud case against crypto entrepreneur Justin Sun, after his investments in the Trump family's crypto firm, World Liberty Financial.

In May, it was announced that a stablecoin launched by World Liberty Financial would be used by an Abu Dhabi firm for a $2bn (£1.52bn) investment in Binance.

Trump has also pardoned founders of the crypto exchange BitMEX, who faced charges related to money laundering, and Ross Ulbricht, founder of the Silk Road, the dark web marketplace known as a place for drug trade.

'I don't know who he is', says Trump after pardoning crypto tycoon