High-powered US Senators on Wednesday unveiled a tough new attempt to punish China and other countries with "misaligned" currencies, but Chinese foreign ministry spokesman Qin Gang insisted such tactics would hurt trade ties.

"We hope the US Congress can view the importance of healthy Sino-US economic and trade relations from a strategic perspective and properly handle frictions... by not trying to solve the issues with pressure," Qin said.

"China has adopted a managed floating RMB (yuan) exchange rate regime and we have already begun reforms of the RMB exchange regime. The reform is ongoing.

"We hope that US side can recognise this in an objective manner."

Premier Wen Jiabao also said in comments published on Thursday that monetary policies would be "moderately tightened".

The bill was unveiled after the US Treasury released a semi-annual report that stopped short of branding China a "currency manipulator", much to the dissgust of some of the legislation's proponents.

However the report said China's tightly controlled exchange rates had led to a variety of economic problems including a massive build-up in currency reserves that posed global risks.

Qin on Thursday refused to address Washington's decision not to brand China a currency manipulator or the criticisms in the report. When asked about the Treasury report, he referred only to China's policies on the yuan.

He also declined to turn up the temperature on prospects of "tit-for-tat" measures if the congressional bill passes and China is slapped with sanctions, after saying on Tuesday that Beijing "would respond in kind" to such measures.

"I already elaborated on our position earlier this week," Qin said.

Critics of the Chinese monetary policy in Washington argue the yuan is undervalued by as much as 40 percent, making Chinese exports unfairly cheap.

They argue that the low currency value is responsible for the loss of millions of US manufacturing jobs and a US trade deficit with China that hit 232.5 billion dollars last year, according to Washington's figures.

But China has repeatedly insisted it will not be bullied into any drastic changes in its monetary policy that could have an adverse impact on its domestic economy.

China manages its currency against a basket of currencies. But it maintains that, after ending the yuan's peg to the US dollar in 2005, its currency has appreciated at a steady pace.

The value of the yuan hit a record high of 7.6258 to the US dollar on Thursday, up 0.69 percent from Monday's rate of 7.6785 to the dollar.

China's official Xinhua news agency highlighted that the yuan had now appreciated by more than 7.5 percent since the peg was removed in July 2005.

However critics in Washington were given further ammunition this week when China released data showing its trade surplus had surged nearly 73 percent in May from a year earlier to 22.45 billion dollars.