Wales scrum-half Mike Phillips has announced he plans to take legal action against Bayonne after confirming he has had his contract terminated by the club.
The 31-year-old intends to issue proceedings against the Top 14 side, who are yet to officially confirm his dismissal for allegedly turning up drunk to a video analysis session on October 11.
Phillips claims he learned of his dismissal from an interview in a French newspaper.
Bayonne chairman Alain Afflelou on Monday morning described Phillips' alleged behaviour as "treason" in an interview with Sud Ouest.
In a statement released to Press Association Sport, Phillips said: "I am extremely disappointed and frustrated by the decision taken by Aviron Bayonnais Rugby Club to terminate my employment.
"I was also disappointed by the fact that I officially heard about my dismissal through an interview given in a French newspaper this morning.
"As a result of discussions with my legal team in France I have now instructed them to issue proceedings against Aviron Bayonnais Rugby Club through the French judicial system."
Phillips was accused of being intoxicated when the squad met on October 11, the morning after Grenoble had been defeated 37-6 in the Amlin Challenge Cup.
Team-mates Dwayne Haare and Stephen Brett also faced the Top 14 side's board last Tuesday to answer for their involvement in the same incident.
Phillips sat out Friday's 24-19 victory over Montpellier, but Brett started the match while Haare was included on the bench.
The two-time British and Irish Lions tourist added in his statement: "I wish to thank my team mates and the many friends I have made in the Basque Country for their help and kindness over the past two seasons.
"I will now wholeheartedly concentrate all my energy and efforts on training with Wales and try to earn a place in the match day squad to help Wales have a successful Autumn campaign against South Africa, Australia, Argentina and Tonga."
Afflelou claimed if the club had not got rid of Phillips he himself would have stepped down, and he does not expect to have to pay the player any compensation.
He told Sud Ouest: "It was him or me. I could not have stayed in a club with such disagreement."
On the subject of compensation, he added: "The procedure will tell. We'll let the lawyers do their work but, at this moment, I do not think so. He is a repeat offender and has been laid off for misconduct.
"But I did not ask the question in these terms.
"From the moment he let us down, his friends, coaches and fans, it was not possible to keep him.
"However, I had great respect and affection for the boy, very respectful, and the player. I had already kept him on a year ago against everyone's advice.
"This summer, I even invited him to my house to offer him a contract extension of two years.
"I trusted him. This is treason."
When asked if he felt Phillips expected the club to take such strong action, Afflelou said: "I hope he does not expect to receive an email of congratulations. With all the sporting problems at the moment, we did not need this type of behaviour. It could no longer be tolerated.
"What he did is inexcusable. And it's not the first time."
He was fined and suspended for 10 days by relegation-threatened Bayonne for an off-field incident last year and was briefly banned from the Wales squad in 2011 following a confrontation with a doorman in Cardiff.