MILAN, March 21 (Reuters) - French media group Vivendi has filed a suit for damages against Italian broadcaster Mediaset over alleged defamation in a lawsuit over a failed pay-TV agreement, a legal source said on Tuesday.
The source, speaking ahead of the opening of a trial in Milan over the failed deal, said Vivendi had not quantified the damages.
Mediaset is seeking court enforcement of an April 2015 contract to sell its Premium pay-TV to Vivendi.
Vivendi pulled out of the accord in July and went on to build a 28.8 percent stake in Mediaset in a move that has angered both the media group controlled by former Prime Minister Silvio Berlusconi and the Italian government. (Reporting by Giulia Segreti and Giancarlo Navach; editing by Paola Arosio)