Sam Tomkins will leave Wigan at the end of the season and is set to confirm a move to Catalans.
Tomkins, 29, returned to the Warriors as a marquee player in 2016 after a two-year stint with New Zealand Warriors in the NRL but will now move on.
Wigan said they offered him a new four-year deal, rather than taking up an option they had in place for 2019, which he turned down.
Warriors executive director, Kris Radlinski, said: ““Wigan had an option on Sam’s contract to keep him as one of our marquee players for 2019.
“After a great deal of consideration, taking all of the factors into account and following an open and honest conversation with Sam, the club felt that the option salary set when Sam returned from New Zealand was too high and opted instead to offer a substantial new four-year deal in its place.
“This new deal was still one of the top three contracts that the club has offered anyone in the past 10 years and was as a marquee player still.
“Sam subsequently told us that the opportunity for him and his family to experience a different culture and lifestyle and to see his kids speaking another language was something that really appealed to him. He also said he wasn’t expecting the Wigan offer to be as good as it was and that had made the decision even more difficult.
“In situations like this, there is nothing that the Club can do other than be generous, fair and wish the player well.
“It came as a surprise to us that another Club had engaged with Sam so early in the year when the deadline for approaching a player under contract is at the end of April. We have made our feelings known about this to the club involved.”
Tomkins has been heavily linked with a move to the Dragons for the past two months, while speculation has linked former Leeds and Castleford full-back Zak Hardaker with a move the DW Stadium.