The World Trade Organization (WTO) ruled in March that China had violated global trade rules with its export limits on rare earth minerals. 

On April 17 China said it would appeal the ruling that was considered a win for Europe and the United States in a case involving unfair trade practices.

"China will make the utmost efforts in the appeals process," Ministry of Commerce spokesman Shen Danyang told reporters at a monthly briefing, Reuters reported.

China, which produces more than 90 percent of the world's rare earths, imposed strict rare earth export quotas in 2010, saying it was trying to curtail pollution and preserve resources.

“Regardless of the appeal's outcome, China's policy objectives to protect the environment and natural resources will not change,” Shen said. “They will also continue to strengthen management of natural resource products in a manner that accords with WTO rules and safeguards fair competition.”

The United States said the export limits allowed China to artificially increase world prices for raw materials crucial for products like hybrid car batteries, wind turbines and energy-efficient lighting, while artificially lowering prices for Chinese producers.

China had been widely expected to lose the case, after a successful challenge two years ago to its export restraints on a different set of raw materials used in the steel, aluminum, and chemicals industries, including bauxite and magnesium.

In that ruling, a WTO panel said China had failed to demonstrate that its export duties were to curtail pollution or conserve resources.