All Blacks coach Hansen to retire after 2019 RWC

Auckland - All Blacks coach Steve Hansen announced on Friday that he will retire after next year's Rugby World Cup in Japan, saying the world champions needed some "fresh thinking".

"I think it's right for the team to have someone new after the World Cup, some fresh eyes, some fresh thinking," he told reporters.

Hansen took over in late 2011 after working as Graham Henry's assistant for seven years and guided the All Blacks to World Cup victory in 2015.

The team has had a mortgage on rugby's number one ranking under his stewardship, never relinquishing the top spot.

He record as head coach is 85 Test victories, eight losses and three draws, a win rate of almost 90 percent.

"His record is unsurpassed... whatever happens next in Steve's career, his place as a New Zealand rugby legend is guaranteed," New Zealand Rugby chairperson Brent Impey said.

Hansen's departure will start a scramble for his position, with his assistant Ian Foster and Ireland coach Joe Schmidt considered the frontrunners to replace him.

"I've got opinions but for once in my life I'll keep those opinions to myself because I don't think it's helpful for the process," Hansen said when asked about a successor.

During his tenure, Hansen has displayed a keen eye for talent and instilled a team ethos of constant improvement.

It paid off after 2015, when a string of legendary players including Richie McCaw, Dan Carter, Ma'a Nonu and Conrad Smith retired but the All Blacks' success continued with barely a ripple.

He had originally intended to step down in 2017, mid-way through the World Cup cycle, but New Zealand Rugby persuaded him to extend his contract until 2019.

He was adamant this time the decision to retire was final.

"What's next? I don't know. So don't bother asking," he said, adding that his priority was to guide the All Blacks to a third straight World Cup in Japan.

A former policeman, Hansen coached domestically with Canterbury and was an assistant at Super Rugby level before moving to Wales in 2001 to work under Henry.

He took over the top job in Cardiff in 2002 but had mixed results before returning to New Zealand two years later to again work as Henry's offsider, this time with the All Blacks.