BEIJING, May 18 (Reuters) - China is committed to improving its exchange rate system based on domestic and international economic conditions, a foreign ministry spokesman said on Tuesday.

Ma Zhaoxu was responding to a question at a regular press briefing about how the yuan will figure in next week's Strategic and Economic Dialogue with the United States.

His comments were a reiteration of the government's long-standing position on the yuan, which has been effectively re-pegged to the dollar since mid-2008 to cushion the economy from the global financial crisis.

The foreign ministry has little, if any, say over Chinese exchange rate policy.

Based on global and Chinese economic development levels and conditions, we will further improve the yuan exchange rate mechanism, Ma said.

He referred other questions about currency policy to the relevant departments. (Reporting by Chris Buckley and Liu Zhen; Writing by Simon Rabinovitch; Editing by Ken Wills)