The U.S. Commerce Department determined that Chinese solar-product imports should be subject to additional tariffs to offset government subsidies, according to an agency document.

The department, which on May 17 announced anti-dumping duties as high as 250 percent on imports from China, found additional state subsidies benefiting the nation’s producers, Tim Truman, a department spokesman, said today in an e-mail.

The Commerce Department in March announced anti-subsidy duties as high as 4.73 percent for the Chinese solar-energy items. The revised determination in a June 22 memorandum would increase the tariffs to 3.44 percent from 2.9 percent on imports from Suntech Power Holdings Co. (STP), and to 5.81 percent from 4.73 percent on imports from Trina Solar Ltd. (TSL), according to a statement yesterday from the Coalition for American Solar Manufacturing. The group, led by SolarWorld AG (SWV), represents companies that produce solar-energy products in the U.S.

The agency’s tariff determinations are preliminary, and no additional duties will be collected at the U.S. border as a result of the new analysis, Truman said. A final decision is scheduled for Oct. 10, he said.

To contact the reporter on this story: Brian Wingfield in Washington at bwingfield3@bloomberg.net

To contact the editor responsible for this story: Steve Geimann at sgeimann@bloomberg.net