Hong Kong equities declined on Monday as investors turned wary ahead of the U.S. Federal Reserve's rate decision and watched for policy direction before China's Central Economic Work Conference later this month.

The Hang Seng Index dropped 319.72 points, or 1.2%, to 25,765.36, while the Hang Seng China Enterprises Index lost 114.77 points, or 1.3%, to 9,083.53.

A majority of more than 100 economists surveyed by Reuters expect the Federal Reserve to cut its benchmark rate by a quarter point at the Dec. 9-10 meeting to support a cooling labour market.

Futures now imply roughly an 86% chance of such a move, suggesting that a hold decision would come as a major surprise, according to a Reuters report.

Closer to home, investors are also watching for policy signals from the upcoming economic conference in Beijing, which is expected to set priorities for 2026.

In corporate news, two companies made their debut on the Hong Kong bourse.

Fabless chip designer Suzhou Novosense Microelectronics (HKG:2676, SHA:688052) closed 4% lower at HK$111 compared with its offer price of HK$116.

Digital teaching and learning firm Shanghai Able Digital Science & Tech (HKG:2687) surged 87% to finish at HK$126.40, well above its offer price of HK$67.50.

Meanwhile, Baidu (HKG:9888) jumped 3% after saying it is evaluating a potential spin-off and separate listing of its non-wholly owned unit Kunlunxin Technology.