MADRID (Reuters) - The European Union has agreed to file a trade suit with the World Trade Organization (WTO) over Argentina's import restrictions, a senior Spanish government source said on Monday.

"The European Union has decided to file a complaint (with the WTO) which will mean, if the EU wins, very serious trade sanctions for Argentina," the source said, adding that the suit would be formally lodged in the next few days.

(Reporting By Paul Day; Editing by Julien Toyer)