BEIJING (AP) — Beijing filed a World Trade Organization complaint Monday over new U.S. tariffs on Chinese tires, stepping up pressure on Washington in the latest in a series of trade disputes.

The conflict is a potential irritant as Washington and Beijing prepare for a summit of the Group of 20 leading economies in Pittsburgh on Sept. 24-25 to discuss efforts to end the worst global downturn since the 1930s.

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.

“China believes that the above-mentioned measure by the U.S., which runs counter to relevant WTO rules, is a wrong practice abusing trade remedies,” said a Chinese government statement quoted by the official Xinhua News Agency.

The WTO confirmed that China has filed a “request for consultations” on the issue.

Beijing’s unusually prompt response to Friday’s tariff decision shows the urgency China attaches to maintaining exports amid slumping global demand.

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

Beijing criticized the move as a violation of free trade and called on other governments to oppose protectionism.

The Office of the United States Trade Representative in Washington said the U.S. had not stepped out of line.

“The United States’ actions on tires are entirely WTO consistent and, indeed, in keeping with an explicit component of the deal China agreed to when it joined the WTO.

They asked for time to phase in certain commitments to open its market,” said spokeswoman Carol Guthrie.

• Joe McDonald