The conflict adds to a series of disputes over poultry, auto parts and other goods that have threatened to strain relations as Beijing and Washington cooperate on complex issues including the economic crisis and North Korea.

It comes as the two world powerhouses prepare for a global economic summit next week.

News of China's filing with the World Trade Organization sent Asian markets down 2 percent and more Monday on worries about the potential impact on the global economic recovery. But investors appeared to take a less dire view of the dispute as the day wore on. European markets were down marginally by late in the trading and U.S. markets were flat by midday.

While China's quick response to Friday's tariff decision threatened to escalate the battle, many private economists said they expected both sides would find a way to avoid a full-blown trade war that would harm producers in both countries.

"The big message from China to the United States is think twice, think three times before repeating this kind of relief for a U.S. industry because if you do this again, we are going to hit you again," said Gary Hufbauer, a trade expert at the Peterson Institute, a Washington think tank.

Economists said that both nations have too much at stake economically to allow the dispute to get out of control.

The United States, as the world's largest economy, represents a huge export market for Chinese products while China is the largest holder of U.S. Treasury securities at a time when U.S. government debt is exploding as the recession and efforts to stabilize the banking system have sent the federal imbalance to more than $1 trillion in the current budget year.

In a speech Monday in New York, Obama said he did not act to be provocative or to promote protectionism. He said expanded trade and new trade agreements are essential to U.S. economic growth and enforcing such agreements is part of maintaining an open and free trading system.

The Chinese complaint to the WTO in Geneva triggers a 60-day WTO process in which the two sides are to try to resolve the dispute through negotiations. If that fails, China can request a WTO panel to investigate and rule on the case.

The U.S. tariffs are "a serious case of trade protectionism, which China resolutely opposes," said a deputy commerce minister, Zhong Shan, quoted by the official Xinhua News Agency.

Beijing's quick response to the tariff decision shows the urgency communist leaders attach to maintaining exports, employment and social stability. Officials have said as many as 30 million laborers lost factory jobs last year as exports plummeted. Many have found new employment, but the government is anxious to avert more job losses.

Chinese leaders are sensitive to public anger, which is easily triggered by suggestions that foreign nations are treating China unfairly. Frustration over the tire tariffs has been fanned by news reports citing a rubber industry group that said as many as 100,000 jobs could be affected and losses to Chinese producers could top $1 billion.

But the decision to go through the WTO could reflect China's desire to confine the dispute and prevent it from disrupting relations with Washington.

Beijing has sometimes retaliated in disputes with the United States in the past by slowing or breaking off talks on other matters. But now the two governments are cooperating on a wide array of issues that they both deem critical, including the global slowdown, climate change and ending North Korea's nuclear program.

Washington and Beijing are key participants in a summit of the Group of 20 leading economies planned in Pittsburgh on Sept. 24-25 to discuss efforts to end the worst global downturn since the 1930s. Both sides want the meeting to be a success.

Obama approved the tire duties to slow the rapid growth of U.S. imports of Chinese-made tires blamed for the loss of thousands of American jobs.

The White House said Obama acted under a provision in the U.S.-Chinese agreement on Beijing's accession to the WTO that allows Washington to slow the rise of Chinese imports to give time to American industry to adjust.

The United Steelworkers brought the tire case in April and said annual Chinese tire exports to the United States tripled from 2001 to 2004 to 41 million. It said more than 5,000 tire workers have lost their jobs since 2004 and said annual imports should be capped at 21 million.

After a U.S. panel recommended tariffs, Beijing launched an unusually high-profile diplomatic offensive to head them off, sending a deputy commerce minister to Washington in August to lobby the White House.

Obama's order raised tariffs for three years on Chinese tires — by 35 percent in the first year, 30 percent in the second and 25 percent in the third.

On Sunday, Beijing announced it would investigate complaints that American auto and chicken products are being dumped in China or benefit from subsidies. The ministry said the U.S. imports have "dealt a blow to domestic industries."

AFL-CIO policy director Thea Lee said the U.S. should not be scared off by China's threats.

"The Chinese government is trying to raise the rhetoric and scare off the United States from using the tools it has negotiated and has it every right to use," she said. "It's a blustering effort."

She called the incident a "short term storm" and said U.S. action against China has been long overdue on allegations of China's worker rights abuses, currency manipulation and illegal trade subsidies.

"This is an extraordinarily imbalanced trade relationship between the United States and China and the U.S. government has been remiss until now in not taking steps to rebalance the relationship," Lee said.

Last month, Beijing was forced to change its tariffs on imported auto parts after losing an appeal of a WTO ruling in a case brought by the United States, the European Union and Canada. They challenged Beijing's policy of requiring automakers to use at last 40 percent Chinese-made components or pay more than double the usual tariff on imported parts.

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AP Economics Writer Martin Crutsinger in Washington, D.C., and Associated Press Writer Frank Jordans in Geneva contributed to this report.