The August trade surplus was $24.97 billion, up from $18.8 billion in August 2006, the Chinese customs agency said on its Web site. That surpassed July's $24.4 billion but fell short of the all-time high of $26.9 billion in June.

Economists expect China's trade surplus to rise steadily despite promises to ease currency controls and restrictions on imports.

The August figure brought China's total trade surplus for the first eight months of the year to $161.8 billion, the customs agency said.

Beijing insists it is not actively pursuing a trade surplus and has tried to cool the boom by repealing rebates of value-added taxes on hundreds of products and imposing new taxes to discourage exports of steel and other goods considered energy-intensive or polluting.

But critics complain that Beijing is adding to its surpluses by keeping its currency, the yuan, undervalued. They say that gives Chinese exporters an unfair price advantage.

The government has let the yuan rise by more than 9 percent against the U.S. dollar since July 2005, which is expected to help narrow the trade gap by making China's exports more expensive abroad and American goods more attractive to Chinese consumers. But critics say the yuan is still undervalued and they want faster action.

The U.S. Senate is considering two measures to penalize China for its currency controls. Those measures have moved ahead despite protests by U.S. Treasury Secretary Henry Paulson, who is conducting a long-range "strategic economic dialogue" with Beijing over trade and other disputes and says sanctions would disrupt that.

The flood of export revenues is straining Beijing's ability to contain pressure for prices to rise. The central bank drains billions of dollars a month from the economy through bond sales and has piled up more than $1.3 trillion in foreign reserves.

China's August exports were $111.3 billion, while imports were $86.4 billion, according to the customs agency.

Europe was China's biggest trading partner, with exports to Europe rising 31.3 percent to $23 billion, while imports were up 21.8 percent at $10.2 billion.

With the United States, its second-biggest trading partner, China ran a $15 billion surplus, according to the customs agency's figures. Exports to the United States rose 16.7 percent to $20.9 billion, while Chinese imports of American goods were up 15.5 percent at $5.9 billion.

China's total trade surplus with the United States stands at $103.3 billion for the first eight months of the year, according to the government. Beijing often reports a much smaller figure than Washington for China's trade gap with the United States.

The United States reported a trade deficit of $232.5 billion with China last year, its biggest ever with any country. The gap this year is expected to exceed that.