OTTAWA, Jan. 7 -- Canada will join a World Trade Organization (WTO) complaint against China over its export restrictions on some raw materials, Trade Minister Stockwell Day said on Wednesday.

Canada is concerned that restraints such as export duties and quotas "are leading to trade distortions in the world market," Day said. "Such measures have caused uncertainty for Canadian producers. We hope that this WTO challenge will persuade China to end these practices."

The WTO set up a dispute panel on Dec. 21 at the request of the United States, the European Union and Mexico. They argue that the restrictions give Chinese domestic industries an unfair advantage since they can buy the raw materials more cheaply.

The raw materials concerned are bauxite, coke, fluorspar, magnesium, manganese, silicon carbide, silicon metal, yellow phosphorus and zinc.

"The (Chinese) measures appear to violate rules on export restraints, as well as the commitment China made when it joined the WTO to not charge export tariffs on most materials," Day's office said in a statement.

Canada is joining the dispute as a third-party participant, as have numerous Latin American, Asian and European countries.