A World Trade Organization appeals panel has found in favor of the United States in a dispute challenging China’s imposition of duties on U.S exports of electrical steel, a steel produced by AK Steel Corp. in Middletown.

The WTO panel said China had acted inconsistently with WTO obligations in imposing the duties. The panel rejected all of China’s claims on appeal.

“This is a victory for the United States as well as for American workers and manufacturers,” said U.S. Ambassador Ron Kirk Thursday. “The Obama Administration will not stand by and allow China to break international trade rules. American manufacturers and workers can compete and win on a level playing field, but China’s unfair duties choked off nearly all U.S. (electric steel) exports to its market.”

In June, the WTO announced that China had violated trade rules with duties placed on American high-tech steel since 2009. In 2008, U.S. exports of the steel to China were valued at $270 million. By 2011 those exports had fallen to less than $3 million.

The electric steel at issue a high-tech, high-value magnetic specialty steel that is used primarily by the power generating industry in transformers, rectifiers, reactors, and large electric machines. AK Steel Corporation, based in West Chester Twp., and Allegheny Ludlum, based in Pennsylvania, manufacture the steel, Kirk said.