It may not be official yet, but if the news coming out of Australia this morning is anything to go by, Sonny Bill Williams will be returning to the Chiefs next year.

According to the Sydney-based Daily Telegraph, the dual-code star wants to prolong his playing career and sees rugby union as a more viable option given the battering his body has taken this year in the ultra-physical NRL.

It is believed the Chiefs have tabled a three-year deal and are on the verge of reigning Williams in over the next fortnight.

However, according to other media sources, it's already a done deal.

Taking to Twitter this morning, Sky Sport NZ commentator Andrew Voss said that Williams was indeed on his way back to Hamilton.

"Whether it gets announced publicly I dont know but Sonny Bill Williams will sign with Chiefs this week," Voss tweeted.

Fairfax Media also understands Liam Messam's re-signing with the Chiefs was a key factor in Williams wanting to return to Hamilton.

Williams, who played 19 tests for the All Blacks, has been in fine form since he returned to rugby league this year with the Sydney Roosters.