Thibaut Courtois and his father Thierry have launched legal action against former Belgium manager Marc Wilmots, who claimed the Chelsea goalkeeper had leaked team information during the 2016 European Championships.
Wilmots had said in an interview with beIN Sports that he was informed Thierry sold Belgium's team news to journalists during Euro 2016.
Wilmots, 49, was sacked following his Belgium's defeat by Wales in the quarter-finals of the tournament, a game in which Courtois was goalkeeper.
"Wilmots - not for the first time - reiterates publicly and intentionally accusations against my honour and reputation as well as my father," Courtois said on social media.
"We decided together to file a complaint accompanied by criminal indemnification proceedings for libel and defamation."
Courtois and Wilmots also had a public falling out with the goalkeeper criticising Belgium's tactics during the Euro 2016.
Courtois, 25, is Chelsea's first-choice goalkeeper and has won two Premier League titles.
