* Hang Seng index ends down 0.56%

* China Enterprises index HSCE falls 0.07% HSBC Holding shares plunge after H1 profit slump

Aug 3 (Reuters) - Hong Kong shares closed down on Monday on weak global sentiment, with U.S. lawmakers struggling to agree to a new stimulus plan, and after a bigger-than-expected drop in profit at HSBC pulled the bank's shares sharply lower.

** At the close of trade, the Hang Seng index was down 137.22 points or 0.56% at 24,458.13. ** Investor sentiment across the region was mixed as U.S. lawmakers struggled to hammer out a new stimulus plan amid a global surge of new coronavirus cases, as the outlook for the world's largest economy dimmed. ** The Hang Seng China Enterprises index fell 0.07% to 10,033.2, outperforming the main index after China's factory activity expanded at the fastest pace in nearly a decade in July as domestic demand continued to improve after the coronavirus crisis. ** Hong Kong-listed shares of HSBC Holdings ended 4.43% lower after the bank reported a 65% slump in first-half pre-tax profit. The bank's shares had earlier fallen as much as 5.72% to HK$32.95, their lowest level since March 2009. ** HSBC shares were the biggest loser on the Hang Seng index on Monday. The top gainer on the index was WH Group Ltd, which added 2.03%. ** China's main Shanghai Composite index closed up 1.75% at 3,367.97 points, while the blue-chip CSI300 index ended up 1.62%. ** Around the region, MSCI's Asia ex-Japan stock index was weaker by 0.42%, while Japan's Nikkei index closed up 2.24%. ** The yuan was quoted at 6.9769 per U.S. dollar at 08:16 GMT, 0.03% weaker than the previous close of 6.9745. (Reporting by Andrew Galbraith; Editing by Ramakrishnan M.)