Samoa coach Matt Parish will let the ink dry on Sonny Bill Williams' landmark Toronto Wolfpack deal before getting in his ear about leading the island nation at the 2021 World Cup.

Williams is set to join the Canada-based Super League team on a historic two-year-deal that will see him acquire equity in the club and earn a reported $10 million in his return from rugby union.

While the 34-year-old has represented the Kiwis in 12 Tests, and the All Blacks on 58 occasions, he also boasts a proud Samoan heritage through his father John and travelled to the island's capital Apia alongside then-CEO David Smith in 2014 to launch the NRL's Pacific Strategy.

His cousin Tim Nanai-Williams has also represented Samoa in both Rugby Sevens and the fifteen-man game.

Match Highlights: Samoa v Fiji

Having seen the influence of Jason Taumalolo and Andrew Fifita in Tonga's rapid rise since they switched allegiance from New Zealand in 2017, Parish believes Williams could have a similar effect on Samoa's own playing stocks.

"I know that although Sonny's New Zealand born but he's very proud of his Samoa heritage," Parish told NRL.com.

"We'll certainly be trying to persuade him to be part of our Test matches at the end of next year and also at the World Cup 2021.

"To have his presence anywhere in any team is enormous. I know the influence he had at the Roosters in '13 when they won the comp with him on board.

"Since then he's been in that fantastic All Blacks system, he's won World Cups there, so his presence in any team, and especially Samoa, would be immense.

"We've already had Marty Taupau come on board with us this year and he's been massive, so positive around the group and you can't have enough of those type of players in and around your squad.

"I know [Samoan players] would all welcome the opportunity to play alongside him."

Samoa was on the end of a heavy 44-18 loss to Fiji last Saturday, an unexpected trouncing given the likes of Taupau, Junior Paulo and Joey Leilua turned out at Eden Park.

Parish is hopeful of securing three Tests for Samoa in 2020, with discussions around end-of-year clashes with New Zealand and Tonga ongoing.

Having Williams on board could have a similar impact for the Pacific nation to that of Taumalolo, whose high-profile shift to Tonga prompted Fifita, Manu Ma'u and Siosiua Taukeiaho to do the same.

Recent Kangaroos debutant Payne Haas also boasts Samoan heritage and struck up a friendship this year with Williams, who also experienced a meteoric rise and conversion to Islam.

I know that although Sonny's New Zealand born but he's very proud of his Samoa heritage Samoa coach Matt Parish

Former Bulldogs teammate Reni Maitua and Nigel Vagana pushed heavily for Williams to join Samoa at the 2013 World Cup.

Williams ended up turning out for New Zealand and claiming player of the tournament honours, while his bombed try against Samoa at Warrington ranks as one of the most enduring memories of the tournament.

"Personally I've never spoken to him but Reni Maitua was part of our squads in 2013/14 and those two are close," Parish said.

"They've won a premiership together and Reni was trying to get him across the line but he chose to play for the Kiwis in '13.

"But 2021 is a different story isn't it? He's not going to get too many other opportunities to play for his Samoan heritage any more so I'm hopeful he'd want to add a Samoan jumper to that great collection he's got already.

"If we could persuade Sonny it would be massive for Samoa and international league in general."

Kiwis coach Michael Maguire wouldn't rule out a return to the black and white for Williams in 2020, but stressed he is "very pleased with the players I have got at this present moment" on Thursday.