Weepu has also been open about his interest in rugby league - spending a week with Andrew Johns and the Newcastle Knights back in January 2007 - and there was talk of a possible code switch when he was dropped for the World Cup.
He was then overlooked for this year's All Blacks squad, placing his future in New Zealand rugby in doubt until he was called in as cover when Andy Ellis and Jimmy Cowan were both injured during the 34-19 defeat to Australia in Sydney last month.
The Wellington and Hurricanes number nine has since deputised for Cowan in Tri-Nations tests against Australia and South Africa.
NZRU general manager of professional rugby, Neil Sorensen, said: "Piri is an outstanding rugby player and to have him play in New Zealand is fantastic for us.
"He has represented New Zealand at the highest level and he has been an influential player for his province and franchise as well.
"We are delighted that rugby will continue to benefit from his talent and experience."