Courtois announced via his Facebook page on Tuesday night that he would be taking action along with his father after comments made by Wilmots in an interview with French television channel beIN Sports.
“Mr. M. Wilmots -– not for the first time -– reiterates publicly and intentionally accusations against my honor and my reputation as well as my father,” Courtois, 25, wrote.
“We decided together to file an official complaint accompanied by criminal indemnification proceedings for libel and defamation.”
Asked about his supposedly difficult relationship with Courtois, a result of the 3-1 defeat against Wales in the Euro 2016 quarter-finals, Wilmots said: “I just have a problem when I… name my team at 6pm and at 6:15pm it is all over social media.”
He added: “That means a player has sold the national team, and that is serious.”
Wilmots claimed that he had proof from “several French journalists” that Courtois’ father Thierry was to blame for leaking the line-up ahead of the match in Lille in July 2016.
“That means that you don’t respect your country. I find that a shame because I have to wait until an hour before kick-off to find out the opposition line-up.”
Wilmots, who had been appointed Belgium coach in 2012, was heavily criticised by Belgian media after the defeat to Wales and was sacked two weeks later despite having two years left on his contract.
He went on to have a spell in charge of the Ivory Coast in 2017, while Spaniard Roberto Martinez succeeded him as coach of Belgium.
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