President Donald Trump offered lukewarm support to Hong Kong pro-democracy protesters Tuesday, saying he trusts President Xi Jinping to resolve the crisis, as US-Chinese trade talks enter their "final throes."

"We're with them," Trump said of the protesters who delivered a landslide victory for pro-democracy candidates in local elections and have battled police for weeks in street demonstrations.

But Trump immediately backpedalled, emphasizing his close ties to Xi and efforts to secure a long-delayed resolution to the trade war between the world's two biggest economies.

US President Donald Trump is giving muted support to Hong Kong protesters as talks on US-China trade go down to the wire
US President Donald Trump is giving muted support to Hong Kong protesters as talks on US-China trade go down to the wire AFP / JIM WATSON

"We're in the final throes of a very important deal, I guess you could say one of the most important deals in trade ever," Trump said.

"It's going very well but at the same time we want to see it go well in Hong Kong. I think it will. I think that President Xi can make that happen. I know him and I know he'd like to make it happen," he said.

Washington and Beijing have delivered a series of positive signals in the last few days about closing in on a partial trade deal, known as "phase one." However, previous predictions of success have repeatedly come and gone.

Last week, Congress passed a bill supporting the Hong Kong protesters. Trump remains on the fence over whether he'll sign the measure, something that would anger Beijing.