Rhys Webb has placed his Wales future in doubt after agreeing to join Toulon when his national dual contract expires next summer.
The Welsh Rugby Union and Ospreys have announced the British and Irish Lions scrumhalf's decision to move overseas for an undisclosed fee after signing a three-year contract.
Warren Gatland is only permitted to select four players from clubs outside of Wales — a number that will drop to two in 2019 — so the news of Webb’s departure is a blow to the Kiwi head coach.
Established internationals Taulupe Faletau, Luke Charteris, Rhys Priestland, Jamie Roberts, George North and Liam Williams are already playing in the Aviva Premiership, while Dan Biggar joins Northampton in June.
“In line with our intention to keep our best players in Wales, every effort to retain the player has been made,” read a statement jointly issued by the WRU and Ospreys.
“While the news is disappointing there is an understanding that on occasion market forces will make this impractical.”
Webb has been Gatland’s first-choice scrumhalf since 2014 and added to his 28 Wales caps during the summer when he made two appearances as a replacement in the Lions’ drawn series with New Zealand.
Injuries have interrupted his Test career, presenting opportunities to rival Gareth Davies, but his energy and running threat mark him out as one of Europe's most dangerous halfbacks.
“It’s a huge wrench to be leaving the Ospreys after spending all of my playing career with the team,” Webb said.
“I have made lifelong friends on and off the pitch and I cannot speak highly enough of the quality of the coaching team, players and all of the staff involved within the Ospreys organisation.
“I will continue to give the region everything I can to make sure we have the best season possible and I would like to conclude by saying a heartfelt thanks to everyone within the Region for helping me achieve my goals within rugby.
“I would like to thank the WRU and the Ospreys for their efforts during this process.”