BEIJING (AP) — The US and China are headed for a possible clash over currency as they open wide-ranging talks on the future of their economic relations.

US officials say Treasury Secretary Henry Paulson will press Beijing to let its yuan rise against the dollar to ease trade tensions at the two-day Strategic Economic Dialogue starting today. American companies contend that China keeps the yuan undervalued, giving its exporters an unfair advantage and adding to its swollen trade surplus.

But with China's exporters suffering, the yuan plunged on Monday in government-controlled trading — a possible message to Washington to go easy on the issue.

"The signal China sent on Monday is: We also have our own political problems and issues in a slowing economic environment," Frank Gong, chief Asia economist for JPMorgan Securities Ltd., said in a report to clients.

Yesterday, the state press made the warning more explicit.

"US urged not to harp on currency issue at talks," said a headline in the China Daily, an English-language newspaper aimed at foreign readers.

The twice-a-year dialogue, launched in 2006, is meant as a relationship-building exercise rather than a forum for negotiation. But Treasury Undersecretary David McCormick told reporters this week that officials at the dialogue would urge China to continue allowing the yuan to rise — a key issue for American lawmakers who are pressing for punitive action if Beijing fails to take faster action on trade complaints.

Both economies are struggling — the US with a recession and China with a sharp slowdown in growth — and how well they keep one of the world's biggest trading relationships stable and productive could be of global importance.

The talks are to cover a broad agenda, including cooperation in energy conservation and environmental protection. Paulson's delegation includes the US secretaries of agriculture, labour and health, the US trade representative, officials of the Treasury and Commerce departments, and others.

Beijing broke a direct link between its yuan and the dollar in July 2005 and has let its currency rise by about 20 percent since then. That has hurt Chinese exporters, which are seeing their goods get more expensive in foreign markets just as demand slows. In a speech on Tuesday, Paulson said it was important for China to stick to its currency reforms and rely more on domestic demand to drive growth.

"As I have said in the past, continued reform of China's exchange-rate policies is an integral part of this broader reform process," Paulson said.

The yuan's fall on Monday was its sharpest one-day fall since 2005, erasing almost one percent of its value against the dollar.

Gong said Beijing's move might have been meant as a warning to President-elect Barack Obama, who has yet to say whether he will continue the dialogue, that talking will be more effective than confrontation.

Chinese exporters have lobbied the government to slow or reverse the yuan's rise against the dollar to make their goods more competitive abroad. But Gong said Beijing understands the problem is lack of demand, not price, and is likely to let the yuan continue to rise over the long term.