"I feel so badly. I spoke to President Xi about it, and I asked to consider his release," Trump told reporters, without specifying when he asked Xi.

"He's an older man, and he's not well. So I did put that request out. We'll see what happens."

Trump had said before he returned to the White House that he wanted to free Lai, a successful businessman who launched the pro-democracy tabloid Apple Daily.

Trump met with Xi in October in South Korea, where he is believed to have raised Lai's case.

Secretary of State Marco Rubio, in an X post shortly following Trump's remarks, said the verdict showed China's determination to "silence those who seek to protect freedom of speech and other fundamental rights."

He noted that China promised to uphold a separate system before Britain handed over the financial hub in 1997.

"Reports indicate that Mr. Lai's health has severely deteriorated during more than 1,800 days in prison," Rubio said in a statement.

"We urge the authorities to bring this ordeal to an end as soon as possible and to release Mr. Lai on humanitarian grounds."

Lai is a devout Catholic, with his case being raised in the United States by an ad hoc coalition both of democracy and press freedom advocates and Christian activists, who form a key base for Trump.

Lai, 78 and diabetic, was found guilty Monday on all three charges in a national security trial and could spend the rest of his life in prison, after already being jailed since his arrest in late 2020.

His conviction is part of a clampdown by China on Hong Kong following mass protests in 2019.