HONG KONG, June 18 (Reuters) - Hong Kong's stock market

will stay open during typhoons and heavy rain effective Sept.

23, a change that will help maintain the global financial hub's

competitiveness, city leader John Lee said on Tuesday.

Lee, who made the announcement during a weekly press

conference, said the move was in line with other cities and

widely supported by traders and banks.

Dickie Wong, executive director of research at Kingston

Securities, said there was already market consensus on the

rollout of the new measure to allow trading under extreme

weather.

"I don't think this measure will greatly help the market

sentiment or trading volume," Wong said, adding he is neutral on

the measure.

"The market is now more concerned about whether the (Hong

Kong-mainland) Stock Connect program can be expanded to include

more companies, such as Alibaba ( BABA ). These measures are

more important for Hong Kong stock market," Wong added.

Shares of the city's bourse operator Hong Kong Exchanges and

clearing ( HKXCF ) eased 0.6% by lunch break. That compared to a

0.2% slip in the benchmark Hang Seng Index.