The United States said it wanted to correct some legal issues in a case that it brought jointly with the European Union and Japan, handing China a heavy defeat over its restrictions on exports of rare earth metals.

The filing said the U.S. concerns would not need to be dealt with if there was no appeal from China. China has not appealed the ruling, but it still has time to do so, with a 60 day window from the time of the ruling on March 26.

In a separate filing, China lodged an appeal in a WTO case that it brought to challenge U.S. punitive tariffs on exports including photovoltaic cells and modules, windtowers and certain steel and aluminum products.

Although Beijing scored a partial victory in that case, by successfully saying the United States had been wrong to punish some Chinese exports twice over, it lost the bulk of the argument against U.S. laws targeting unfair trade subsidies.

(Reporting by Tom Miles; Editing by Alison Williams)