The winger has reportedly signed a two-year deal to play for the Wallabies and Queensland Reds starting in 2021.
“The Storm has been wonderful to me, and I’m continuing to make great memories here,” Vunivalu said.
“However, the offer from rugby union was too good for me to refuse, especially considering I have a young family who I want to do the best for.
“I was a rugby union player before switching to league and always thought of going back to rugby as an option for my career and I never wanted to play for another NRL club.
“I’d hate to have to go up against Storm and my mates.”
Storm chief executive Dave Donaghy said his club could not match the size of the offer from the Wallabies.
“Suli has received an offer from rugby union which we couldn’t compete with financially,” Donaghy said.
“It’s always disappointing to lose quality players but we understand Suli’s decision.
“Importantly he has expressed his total commitment to Storm for the next 12 months and we expect he will again play a key role in our 2020 campaign.
“We have had experience in the past with players signing deals for the future but remaining with Storm to see out their current contracts.
“Players such as Cooper Cronk, Tohu Harris and Marika Koroibete come to mind. And in all of those cases, those players have excelled in their final year.”
With Melbourne Rebels having several outside backs including former Storm winger Marika Koroibete, the Reds will pick-up Vunivalu who played high school rugby on scholarship in New Zealand before Storm’s talent scouts signed him for their under-20 side.
The 24-year-old winger made a stunning debut for the Storm in 2016 after injuries saw them forced into bringing the injury prone flyer into the first grade team and he scored within minutes of the kick-off and went onto set a first-year record of 23 tries from 21 games.
Vunivalu has gone onto score 75 times in 95 appearances and play in the club’s 2017 premiership and their 2016 and 2018 grand final losses, his wing tandem with Josh Addo-Carr made the Storm’s attack one of the most potent in the NRL.
Koroibete overcame a difficult adjustment to rugby union to star this past season winning the John Eales Medal as the Wallabies best player through the international season and Rugby World Cup.
Vunivalu said he remained fully focused on the Storm.
“Now this decision is public, I”m concentrating 100 per cent on my final year in Melbourne and looking forward to doing the best I can for the boys, the coaches and all our members and fans,” Vunivalu said.
“I won’t be making any further comments on rugby until the NRL season is done.”
Roy Ward is a Sports writer for The Age.