TJ Perenara believes it's now or never if he makes the switch to rugby league.

The All Blacks halfback is in discussions with NRL club the Sydney Roosters about joining them when his deal with the Red Hurricanes in Japan ends next month.

The 29-year-old is yet to decide whether he'll accept the offer but says if he re-signs with New Zealand Rugby, he'll probably never play professional league.

"No decision yet. There's a few different scenarios on the table but in all honesty, my wife and I haven't come to a decision," he told NZME.

"I would be doing the club and the boys that I work hard with an injustice by focusing on anything else besides our games coming up. I wanted to make a conscious decision to focus on the games at hand and when there's some time to put some thought into some other things, do that in due time.

"If I don't make a decision and be part of an organisation this year, I don't know if I will do it again. It will be a commitment one way or the other. Committing to New Zealand Rugby, to home and the [Wellington] Hurricanes will take league off the table for my career," Perenara said.

Perenara said he has been doing homework on the hooker position in the 13-man code, talking to current players.

"I've reached out to some boys with suggestions on who to watch. Who people think are the better nines in the game, who play the game well, what people expect from nines in the game. Just trying to get some dialogue into what firstly what other nines think other nines are good at and where I can work on my game before making a decision.

"And secondly what halves want from their nines. What do they expect from their nines in passing, kicking, running the game and organising. Just trying to get that knowledge to see where I could best fit."

Earlier this month Hurricanes CEO Avan Lee told NZME they are keen to re-sign Perenara.

"I had a long Zoom call with him and his manager and spoke about the Hurricanes and the All Blacks. We didn't talk about rugby league, just talked about the Hurricanes and obviously we're keen to get him home. He said he's keen to be a Hurricane and be an All Black again," Lee says.

"He's got choices and if there is truth to the Roosters rumour then obviously he's more than able to have that conversation, so we only control our conversation with TJ and we know how much he loves the Hurricanes.

"If he comes home and is playing anywhere near what he normally would then he'll be in the All Blacks as well at Rugby World Cup 2023."