Wolfpack coach Brian McDermott is understood to have flown to Japan to meet with Williams, who is reportedly set to be offered a $9 million, two-year deal to finish his playing career in Canada.
The newly promoted Super League club has also been linked to NFL hopeful Christian Wade, a former England rugby union winger who is on the Buffalo Bills practice squad, but believe Williams could have a similar impact for the code in North America to David Beckham signing for LA Galaxy.
However, he is also viewed as a major drawcard for rugby union in France ahead of the 2023 World Cup and coaches from two of the country's Top 14 clubs are also understood to have flown to Japan to meet with him.
Williams, who is expected to make his final appearance for New Zealand in the Rugby World Cup’s third place play-off, used his final pre-match press conference at the tournament to speak out about the lack of coaches of Pacific Island or Maori heritage in the All Blacks set-up.
All Blacks coach Steve Hansen was an assistant to Sir Graham Henry before being appointed to the top job and he has publicly backed his assistant Ian Foster take over after the World Cup.
None of the trio are Pacific Island or Maori heritage, nor are Hansen’s other assistants, Scott McLeod and Mike Cron.
Williams has been a strong advocate for the Polynesian community during his time in New Zealand rugby union and believes the large number of players with Pacific Island or Maori heritage in the All Blacks team warrants greater influence.
It’s an issue Williams is passionate about and the coach who persuaded him to quit the Bulldogs and join Toulon in 2008, Tana Umaga, is of Samoan heritage, while he also shares a close relationship with his former Chiefs mentor Dave Rennie, who is of Cook Islands heritage.
The 34-year-old, whose omission from the All Blacks starting line-up against England has drawn criticism, holds a Samoan passport and visited the island nation to launch the NRL’s Pacific Strategy in 2014, while playing for the Roosters.
His cousin Tim Nanai-Williams plays rugby union for Samoa and Williams has previously considered representing the country whose tribal tattoos he has inked on his right arm and calf.
Under rugby union’s eligibility rules Williams can only play for New Zealand but in league he would qualify for Samoa as well as the Kiwis through his father John.
Pacific nations want rugby union to adopt similar eligibility rules to league after the failure of Fiji, Samoa and Tonga at the World Cup, while player payments and a lack of regular matches are major concerns.
In comparison, the International Rugby League and other bodies, including the NRL, have provided support for the Pacific nations through measures such as:
eligibility rules enabling players to switch between Australia, England or New Zealand and a tier two nation they also qualify for;
expanding the mid-season Pacific Test concept into the Oceania Cup, which ensures each nation plays a minimum of two Tests per year, and;
Participation payments of $2,500 per Test for all players in the Oceania Cup, including Tonga, Samoa, Fiji and Papua New Guinea.
Samoa play Fiji at Eden Park on Saturday in the opening match of a triple-header featuring Australia-Tonga and New Zealand-Great Britain Tests.
After beating Papua New Guinea in June, Samoa will secure a place in Pool A of the 2020 Oceania Cup with Tonga and New Zealand if they also defeat Fiji. The winner of Pool B replaces as Australia as they have a Kangaroo tour scheduled for the end of next season.
A Fiji team will join the NSWRL’s Ron Massey Cup next season with a view to gaining promotion to the Canterbury Cup, while the PNG Hunters play in Queensland’s Intrust Super Cup.
Toronto coaching director Brian Noble is in Auckland for the triple-header as a member of the BBC commentary team and he confirmed Wolfpack’s interest in Williams.
“Who wouldn’t want to sign Sonny Bill Williams,” Noble told the Five Live Rugby League podcast.
“One of our mantras clearly at Toronto is to bring the best we possibly can bring in relation to a guy who can put bums on seats in the Super League. I think we are trying to make a decision that is good for the game.
“Our aspirations are to bring an impactive, world-known, world-great, current great in relation to heritage and presence in the game of rugby generically across the world and a recognisable name so clearly we are interested in trying to secure his services but we are in a competition with others.
“To have somebody of his presence, who has just featured in his third World Cup, would be massive and massive not only for the game in Canada but for the game in the UK too.”
The ambitious club, which is owned by Australian mining magnate David Argyle, is looking to play matches in Europe, including Dublin, Amsterdam and at Barcelona’s Nue Camp, where Catalans this year drew a record Super League crowd against Wigan.