Hong Kong shares closed down on Thursday, led by tech stocks, as investors fretted that intensifying competition among e-commerce giants could squeeze profit margins.

The benchmark Hang Seng Index ended down 151.47 points, or 0.63 percent, at 24,069.94.

The Hang Seng China Enterprises Index fell 0.88 percent to end at 8,648.44 while the Hang Seng Tech Index slid 0.67 percent to end at 5,233.71.

E-commerce giant Alibaba shares fell nearly 3 percent, leading declines in Hong Kong, after the company announced a 50-billion-yuan subsidy programme to merchants and customers on Wednesday.

"Alibaba's plan to offer US$7 billion of subsidies for food delivery and online retail implies competition is heating up again among China e-commerce companies," said UBS analysts.

Shares of on-demand delivery giant Meituan dropped 2.5 percent while JD.com fell 2.1 percent.

Biotech stocks, however, rose, with Ascentage up 6.2 percent.

Mainland stocks closed higher, with the benchmark Shanghai Composite Index up 0.18 percent to 3,461.15 and the Shenzhen Component Index 1.17 percent higher at 10,534.58.

The ChiNext Index, tracking China's Nasdaq-style board of growth enterprises, gained 1.9 percent to close at 2,164.09.

China's services activity expanded at the slowest pace in nine months in June, as demand weakened and new export orders declined amid a fragile trade truce with the United States, a private sector survey showed on Thursday.

China's semiconductor shares were little moved after US chip design software developers said they have received notices lifting restrictions on exports to China.

China is assessing the trade deal between the United States and Vietnam and will safeguard its own rights and interests if needed, a spokesperson for the Commerce Ministry said on Thursday.

Healthcare shares led gains onshore, up 1.2 percent, as Beijing ramped up policy support for the country's innovative drugs. (Reuters/Xinhua)