Ben Barba is returning to the NRL after agreeing to join the North Queensland Cowboys for the 2019 campaign.
The 29-year-old has not played in the competition since the Cronulla Sharks released him in 2016 following a positive drugs test.
Barba, who had helped the Sharks win the NRL title in 2016 before he was let go, changed codes to play rugby union for Top 14 side Toulon before joining Super League side St Helens in May 2017.
The full-back had signed a two-and-a-half-year contract with Saints and is the Super League's leading try-scorer this year.
Barba's performances helped Saints win the League Leaders' Shield in 2018, and they face Warrington Wolves for a place in next month's Grand Final.
However, Barba will return to the NRL at the conclusion of the campaign and play for a Cowboys side that will lose Johnathan Thurston to retirement following this year.
"Playing in England and St Helens in particular has been a wonderful experience for myself and my family," Barba said at Saints' end-of-season awards ceremony.
"I cannot thank the club, fans and most importantly chairman Eamonn McManus, CEO Mike Rush, coach Justin Holbrook, my team-mates and their families on how they welcomed me and my family into the club.
"They supported me when I needed it most and I am appreciative of the understanding and compassion in allowing me to return home.
"I want to finish the season off playing my best football for the club and fans and hopefully capping off a successful season."
The Sharks had already ruled themselves out of the running to bring Barba back due to salary-cap restrictions.
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