Willis, 29, played fives tests for the All Blacks. But a run of injuries bumped him down the pecking order behind Keven Mealamu, Andrew Hore and Anton Oliver.

All five of Willis' tests were in 2002.

He has played 38 games for the Chiefs and 26 for Waikato after moving north from Dunedin. All up, he has appeared in 61 Super games.

In his two mid-week games for the All Blacks, Willis was thrown the captaincy at the age of just 22.

Blues utility back Isa Nacewa, 25, announced this week that he was joining Irish side Leinster.

Nacewa and Willis are understood to among the first of several leading Super 14 players heading overseas, mainly to Europe, this year.

There have been suggestions that All Blacks Jerry Collins and Daniel Carter and Blues captain Troy Flavell will join the exodus.

After last year's World Cup such players as Doug Howlett, Byron Kelleher, Anton Oliver, Carl Hayman and Chris Jack headed for northern hemisphere clubs.