Ultan Dillane will leave Connacht at the end of the season after signing a contract with an unnamed overseas club.
The towering lock leaves the province 10 years after joining their academy, with reports indicating that he could be set to join Ronan O'Gara's La Rochelle.
The 28-year-old Kerry native's Ireland career will be put on hold, having made 19 appearances in green since his 2016 debut, but Dillane is looking forward to a new challenge.
A Dillane statement said: "This has been one of the hardest decisions I’ve ever had to make, but ultimately I feel that the time has come for me to experience a new challenge in my career.
"I am forever grateful to all the coaches and wider staff at Connacht I’ve worked with these past 10 years. You have all helped make my dream of becoming a professional and international rugby player a reality. I’ve also been fortunate to play alongside some incredible players both for Connacht and Ireland, and I have made some friends for life.
"The Connacht supporters are among the best in the world and I’d like to thank them for all the support they’ve given me too. The West of Ireland will always be a special place to me.
"I will be giving absolutely everything to finish my time in Connacht on a high, and help all of us to go on to have a really successful season. This is a team on the up and I’ll forever be a Connacht Rugby supporter.”
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