The Panthers confirmed that the 2023 Golden Boot Winner approached the club this week with a request to return home to New Zealand on compassionate grounds.
The three-time premiership winning prop has signed a four-year deal with the Warriors from the start of 2025.
“We’re absolutely delighted to be able to sign James,” said Warriors CEO Cameron George.
“It’s a huge signing for us, undoubtedly one of the biggest in our club’s history.
“To be able to add a player of his calibre and standing to our squad is a tremendous boost for 2025 and beyond. He’s such a highly-respected player and leader.”
“It’s going to be fantastic having James with us. He’s one of the game’s elite players, a super tough forward who sets and demands the highest standards,” added Warriors coach Andrew Webster.
“I loved working with him at the Panthers and we really look forward to bringing him into our system from next season. He’ll add terrific value to our roster, to the club overall and he’ll also be invaluable as a mentor for our young players coming through.”