Closing arguments are due to begin in the national security trial of Jimmy Lai, 77, a fierce critic of China’s Communist Party.

United States President Donald Trump has renewed his promise to “save” jailed Hong Kong tycoon Jimmy Lai, who is on trial for alleged national security crimes over his pro-democracy activism and antipathy towards China’s Communist Party.

“I’m going to do everything I can to save him. I’m going to do everything … His name has already entered the circle of things that we’re talking about, and we’ll see what we can do,” Trump told Fox News Radio in the US.

Trump’s remarks came as closing arguments in Lai’s high-profile trial.

Closing arguments have been pushed from Friday to Monday after Lai’s lawyer said he had experienced heart palpitations.