Taking the first formal step towards litigation, the European Union's executive arm said it wanted the WTO's dispute settlement body to consider the case on September 28, and expected the United States and Canada to do the same.

"We have tried again and again to find an acceptable negotiated solution to this issue and without Chinese engagement we have no alternative but to take this course of action," EU Trade Commissioner Peter Mandelson said.

The EU claims that European car manufacturers are put at a disadvantage compared to local producers when they import spare parts into China because of the country's tariff regime.

The issue marks a new point of conflict in the European Union's trade relations with Beijing after disputes over Chinese clothes and shoe imports into the 25-nation over the last year.

According to the commission, China levies tariffs on specific combinations of imported car parts as though they were "complete vehicles" even when they do not make up a whole car.