All Black veteran Ben Smith will play for French club Pau after the 2019 Rugby World Cup but flanker Ardie Savea has backflipped on an agreement to join the same club and re-signed with the NZRU.
In other big signing news, World Rugby player of the year Johnny Sexton has extended his contract with the Irish Rugby Football Union until the end of the 2020/21 season.
Pau club president Bernard Pontneau told French broadcaster RMC Sport on Tuesday that Smith will join the Top 14 club after next year's Rugby World Cup.
Smith lifted the Webb Ellis trophy in 2015 and the 32-year-old has featured on 76 occasions for his country, scoring 33 tries since making his international debut in 2009.
He will move to an unnamed Japanese club after finishing the 2020 Top 14 season and will be unable to feature for his national side while playing outside of New Zealand.
"It's a great satisfaction. He will have an impact on the squad and considering his calibre it will allow him to help our youngsters," Pontneau said.
On the other hand, New Zealand back-rower Ardie Savea will not join the club who sit in 11th place in the table, despite originally agreeing a three-year deal in the autumn.
The 36-time All Black has decided to re-sign with the New Zealand Rugby Union.
Sexton, 33, was crowned as the world's best player for 2018 last month after leading Ireland to a Six Nations Grand Slam, a Test series victory in Australia and a first ever win over New Zealand on Irish soil, as well as spearheading Leinster's Champions Cup and Pro14 success at club level.
"I am delighted to sign a new IRFU contract to continue to play for Leinster and Ireland. It is where I have always wanted to play so I am delighted to extend," said Sexton in an IRFU statement.
"We get looked after extremely well here and it is an exciting time for Irish rugby. I am looking forward to hopefully being a part of that over the next few years"
The 33-year-old fly-half has won 78 caps, scoring 738 points, and has twice toured with the British and Irish Lions.
"Johnny's hunger and drive mark him out as a truly world-class competitor," said IRFU performance director David Nucifora.