Sonny Bill Williams has mapped out his footballing future through to 2016.

But there's frustration within the New Zealand Professional Boxing Association that he hasn't confirmed his plans for its heavyweight title, which he holds.

Williams, who is in camp with the Kiwis as they prepare for their defence of the Rugby League World Cup, is staying with NRL premiers the Sydney Roosters next year before a projected return to rugby union.

With the 2015 Rugby World Cup and the 2016 Rio Olympics sevens tournament among his targets, he told journalists at the weekend that he won't have time to box in the next three years.

Meanwhile, Joseph Parker's defeat of Afa Tatupu last Thursday to claim the rival New Zealand NZNBF belt also made him the NZPBA's No.1 contender and a challenge was issued to Williams camp.

But NZPBA national secretary Pat Leonard is upset there's been no word back from Williams or his manager, Khoder Nasser, which leaves the association in limbo.

"He hasn't come back to me or the association," Leonard said on Tuesday.

"That is the only way we will find out for definite."

Under NZPBA rules, after receiving a challenge from a credible opponent, Williams has 12 months to defend the title, but that bout can be against any fighter ranked in the top 10.

If he retains the crown, he then has to fight the No.1 contender.