* HKEX trying to develop mainland metals business
* But CEO says plans will take time
* Says not to expect 'big bang' news from bourse at LME Week Asia (Adds comment, detail)
HONG KONG, May 17 (Reuters) - The head of Hong Kong Exchanges and Clearing on Thursday said it would take time for the group to develop its metals business on the Chinese mainland.
That includes plans such as developing its mainland commodity business in Qianhai in southern China and starting warehousing through its London Metal Exchange operations.
"We need a lot of patience. We need to develop the relationship and trust," HKEX chief executive Charles Li said at a metals industry event in Hong Kong hosted by the bourse.
The LME, bought by HKEX around five years ago, has for years pursued its ambition to set up warehouses in China, the world's biggest consumer of metals. But it has been without success so far as Chinese regulators have nurtured mainland exchanges.
HKEX is also focusing on how to better connect China's domestic commodity market with the LME and other international markets, while its onshore commodity business at its Qianhai exchange is still waiting for regulatory approval.
Li added that LME week Asia would not see a "big bang" announcement from the bourse.
"This year it's more of a work in progress," he said. (Reporting by Melanie Burton and Tom Daly; Editing by Joseph Radford)