Petersen, who was due to come off contract at the end of the season, played his final NRL game for the Titans against Newcastle on Saturday night and will play out the year with Wakefield.
Titans managing director Michael Searle said the club did not want to stand in the way of Petersen taking up an "outstanding" overseas deal.
"Matty has been fantastic for the club," Searle said of the former Parramatta Eel.
"His passion and commitment both on and of the field have been outstanding.
"It was a difficult decision for the club to let him go but, given we were uncertain about what would happen next year, it would be unfair on him and his family to drag this out.
"He's secured an outstanding deal in the United Kingdom and it would have been difficult for us not to accept his request.
"We've done this in good faith to Matt and his family."
Petersen said the offer, which was first raised only a week ago, was too good to turn down.
"It just came about in the last seven days. It took me by surprise too, but I've had a great time here and (the Gold Coast) is where I'll come back to live afterwards," said Petersen.
"It's a two-and-a-half year deal so I've got to take it while I still can.
"At the end of the day I've got to look after the family.
"It's a new challenge ahead and it's exiting."
Searle said the 28-year-old may be welcomed back to the club in a non-playing capacity in the future.