Trump says Nvidia boss told him he had no idea woman he had affair with was Chinese spy

Donald Trump has said the boss of Nvidia, whose affair with an alleged Chinese spy is being investigated, told him that he had "no idea she was a spy".

The US President said he spoke with CEO Jensen Huang on Monday following reports that the US believed he had been targeted in a Chinese espionage campaign.

"I asked him that question, 'Did you have any idea she was a spy?' He said 'I had no idea she was a spy' and I really believe him," Trump told reporters.

Trump said the FBI was also investigating the affair. China has rejected claims that Huang was targeted, with its foreign ministry saying the allegations were "entirely groundless, speculative and intended to smear and malign China".