WASHINGTON — The World Trade Organization sided with the United States on Friday in a dispute over punitive Chinese tariffs on American exports of cars and sport utility vehicles.

China, which joined the W.T.O. in 2001 in a move that signaled its broader entry into the global market system, had already lifted the tariffs involved in the dispute, but American officials declared victory, citing the decision as the latest in a series of rulings that it has won against Beijing.

“China has had 14 years — 14 years — to start playing by the rules,” said Senator Debbie Stabenow, Democrat of Michigan, at a news conference in Washington. “But instead we see illegal and improper activities over and over again. As long as China keeps up this illegal behavior, we can and must respond with these kinds of strong enforcement actions.”

The decision comes against a backdrop of increasing commercial tensions between Beijing and Washington. The Obama administration has criticized China for its supposed state-sponsored spying on American firms, and challenged its willingness to play by the rules over trade in cars, steel and chickens and other goods. The broader diplomatic situation has become tense as well, over concerns about how to deal with North Korea and whether China’s territorial ambitions in the South China Sea and elsewhere threaten United States allies in the region.