Lesley Vainikolo reckons "the time is right" to forge a new career in rugby union.

The Tongan powerhouse was unveiled as a Gloucester player at a press conference this afternoon as he spoke for the first time about how he sees his future in the 15-man game.

Vainikolo takes up his three-year contract at Kingsholm on July 1 and he explained: "That gives me a full pre-season and a chance to get a head start in rugby.

"It was a difficult decision to make but I just got the feeling it's time to move on and I need a new challenge. I've done everything in rugby league and am happy with what I've done.

"I achieved my goals - and the Bradford goals as well - which was to win championships.

"There's been records like becoming the first team to win the treble in 2003, which was sweet. It was great in 2005 as well when everyone wrote us off and we proved them wrong, while I can say Bradford Bulls are the best rugby league club in the world.

"But the competition is getting harder and harder - and I'm getting older and older! You have to think about your future and this was the time to give union a go.

"I've got to thank all the fans who have believed in me over the years through my ups and downs. They've been amazing."

The scoring sensation, with 143 tries in 146 Bulls games, is hoping to finish with a flourish. He has six matches left before moving to his new home in Cheltenham and has his eyes on reaching a magical 150 touchdowns.

"I'm trying for it," he laughed, with his final fixture set to be at Headingley next month. "And it'll be great finishing off by having one more crack at Leeds on a high like that."

Vainikolo, 28, has played union before as a kid and is confident of making the transition with Gloucester, who lost the Guinness Premiership final to Leicester on Saturday.

They already have former Bulls winger Karl Pryce on their books and boss Dean Ryan said: "Lesley has the potential to be a world-class player in rugby union.

"The modern game requires power as well as pace, which Lesley will bring us. Both he and Karl Pryce should increase the physicality of our backline alongside our existing options."

Vainikolo can see resemblances between his new club and Bradford.

"I saw Gloucester and after I'd spoken to a few people, including Karl, I realised it was quite similar," he says.

"I couldn't ask for more than that. Bradford are a family team and they have been great to me and my wife.

"Gloucester are like that and I thought it was the right place for me to start my union career.

"They showed their potential by getting to the final and hopefully next year we can go all the way."

Vainikolo would like to represent Tonga in the World Cup later this year but admits: "I'm am just concentrating on to breaking into the Gloucester team. Hopefully if anything else does happen, then great, but I've got to get to know the boys here first."