BEIJING (AP) – The United States and China pledged closer co-operation on financial regulation and energy yesterdday but made no breakthroughs on currency exchange rates in a high-level dialogue overshadowed by Korean tensions.

China agreed to modify a policy on promoting domestic technology development that Washington and others complain might hamper trade. US officials said they still have concerns and the two sides will hold more talks in coming months. "This round of the dialogue did not solve all our problems but did produce concrete results," US Secretary of State Hillary Clinton said after the second annual meeting of the Strategic and Economic Dialogue.

Both sides praised the dialogue as a vital tool for easing trade strains and promoting economic and political ties. But the talks also highlighted the divisions between them and Beijing's growing assertiveness in promoting its own interests. The meeting produced no progress on China's currency controls, a key irritant in relations with Washington. Chinese President Hu Jintao promised currency reforms on Monday but gave no time frame and said Beijing would set the pace of change.

Washington and other trading partners complain China's yuan is undervalued, giving its exporters an unfair advantage. The yuan has been frozen against the dollar since late 2008 to help Chinese manufacturers compete amid weak global demand.

Treasury Secretary Timothy Geithner, the US economic envoy to the dialogue, declined to say when his department might release a report on whether Beijing is a currency manipulator, which could lead to sanctions. The report was due on April 15 but Geithner delayed it, saying international meetings this year were a better way to advance Washington's position.

The two governments announced modest agreements to co-operate in banking and financial market regulation and development of alternative energy.