Julien Bardy will leave Clermont Auvergne to join Top 14 rivals Montpellier at the end of the season after agreeing a three-year deal.
Montpellier on Thursday confirmed that the flanker will leave the league leaders to make the move to Altrad Stadium on a contract that will run until 2020.
Bardy, currently recovering from a shoulder operation, joined Clermont back in 2009 and is relishing the prospect of starting a new challenge next year.
He said: "I am honoured and very happy to join the MHR next season, Montpellier is one of the top clubs in the Top 14. I will do everything possible to bring the maximum to the team."
The 30-year-old was injured in the first half of a 49-33 victory over Bordeaux-Begles on October 22 and Clermont revealed this month that he is expected to be out for up to four months.