Brent Impey says the "proper process" to replace New Zealand coach Steve Hansen will not begin until after next year's Rugby World Cup.

Hansen announced his plan to depart after the tournament on Friday, bringing an end to a tenure that has so far featured one world title and six Rugby Championships.

However, despite being granted an extended period by Hansen to now make a move on the next coach, Impey is keen to first ensure there is no distraction from the All Blacks' efforts in Japan.

The All Blacks chairman acknowledges that he and his colleagues are aware of the leading candidates and some conversations will take place, but an appointment will wait.

"All potential candidates we have relationships with," Impey told reporters on Friday. "They'll now all know, as a result of today, so I don't think we'll now have to put out an advertisement for the gig.

"We will be talking to them and the proper process will start after the World Cup. We've made a very deliberate move that we're not going to engage in a formal process while we've got the runway through to the end of Tokyo.

"We don't want any distractions from the team's performance. After that, we've got time before things kick off in 2020."

New Zealand CEO Steve Tew added that they will look to get Hansen's advice, but the coach will not be involved in the recruitment process.

Asked if Hansen could now instead take up a more senior role, he explained: "Whenever you lose someone who's been around for a long time, there's a desire to (a) protect what they know and make sure it doesn't go somewhere else and (b) to make sure that we transition.

"I know Steve's been very strong on growing the people around him and the succession process inside that team is well advanced.

"But we'll leave that conversation until after the Rugby World Cup and then we'll come back to it and see what he wants to do."

Hansen was himself asked if assistant Ian Foster, a mooted option, would be suited for the role, but the 59-year-old would prefer to leave the decisions to others.

"I think [Foster] would be a great head coach," Hansen said. "He's developed as a coach, as a man and he's got some great qualities.

"But I don't think it's right that I sit here and say, 'that guy should do the job' or 'that guy should do the job'. I think it's the rugby union's job.

"I've got my opinions and, for one of the very few times in my life, I'll probably keep that opinion to myself. I don't think it's right for the process."