The Hang Seng Index climbed 0.4 percent, to 26,041.
The market was helped by a late surge after Beijing announced the US goods purchase, the latest sign of easing tensions between the world’s two biggest economies.
China Resources and Tencent lead the gains, rising 2.3 percent and 1.2 percent respectively.
But the announcement came too late for Shanghai, which ended down 0.9 percent with traders cautious ahead of a weeklong holiday. The Shenzhen Composite Index shed 2.5 percent, to end at 1,597.
Most Asian markets advanced after upbeat comments from US President Donald Trump that a trade deal with China could come sooner than expected.
Tokyo closed up 0.1 percent, with steelmakers and auto manufacturers climbing on the brighter outlook for US trade deals.
Elsewhere, Sydney slipped 0.5 percent while Seoul ended marginally higher and Singapore was flat. Jakarta was up more than one percent and Mumbai was 0.9 percent higher.
“Markets have been swayed by the president’s remarks every day… In the latest move, sentiment got a boost from the president’s positive remarks” on trade, said Makoto Sengoku, market analyst at Tokai Tokyo Research Institute.
“It eased worries for now that the spat would weigh on the global economy,” he said.
Crude prices slipped after an unexpected rise in US inventory and a swift recovery in Saudi Arabia’s output following the September 14 attacks. On forex markets, the pound was little changed. (AFP)