The European Commission wrote in a statement June 30 that it is seeking a WTO ruling because "extensive bilateral discussions over the last months with Moscow have not brought any results."
Russia closed its market to live pigs and pork products in January, after four cases of African swine fever were detected in wild boars on the Lithuanian and Polish borders with Belarus.
Brussels says the move is unjustified and a breach of Russia's WTO commitments.
Russia accounts for almost 25 percent of EU pork exports.
The trade spat comes as relations between Russia and the West have plummeted over the crisis in Ukraine.
