By Shashwat Chauhan

Oct 8 (Reuters) - U.S.-listed shares of Chinese companies fell on Tuesday, tracking an underwhelming start for Shanghai markets after a week-long break, as investors worried over the lack of new stimulus measures to power an economic recovery.

American Depositary Receipts (ADRs) of Chinese e-commerce giants Alibaba Group dropped about 8% in premarket trading, while JD.com and PDD Holdings declined 10.9% and 10.6%, respectively.

China's stock markets climbed to their highest levels in more than two years at the open, but lost steam after economic planner chairman Zheng Shanjie failed to detail sufficiently big or new measures.

"This morning's briefing from the Chinese government didn't really seem to give investors much new stimulus measures," said Christopher Peters, trading floor manager at Accendo Markets in London. "The concern may well fall towards whether or not this would be sufficient to stop any sort of property problems in China."

Shares of China-exposed assets such as European luxury firms and commodities tumbled . They had rallied, along with domestic and U.S.-listings of Chinese firms, toward the end of last month after Beijing introduced a bevy of stimulus measures to prop up its ailing economy.

China's blue-chip CSI 300 jumped more than 10% intraday on Tuesday, but surrendered some gains mid-day and closed up 6%.

Equities in Hong Kong , which remained open all through last week, slumped more than 9% and clocked their worst single-day showing since 2008.

The downbeat mood spilled over to the U.S. markets. Chinese electric-vehicle maker Nio shed 10.6%, gaming company Bilibili lost 15.7% and search engine giant Baidu

eased 9.1%.

The iShares MSCI China ETF fell 12.9%, while the tech-focused KraneShares CSI China Internet ETF slipped 12.1%.

Other China-exposed industries also came under pressure. Copper producer Freeport-McMoRan slipped 4.1%, while luxury firm Estee Lauder eased 3.5%.

(Reporting by Shashwat Chauhan in Bengaluru; Editing by Sriraj Kalluvila)

((Shashwat.Chauhan@thomsonreuters.com;))