Rugby World Cup: All Blacks legend Dan Carter tags France as early favourites, after resounding Six Nations triumph

All Blacks great Dan Carter has joined the chorus of pundits declaring France as firm favourites for next year's Rugby World Cup.

France have moved past the All Blacks into second on the world rankings, after their Six Nations triumph over the weekend, and the next 18 months loom as a crucial period for Ian Foster's men to put themselves back in contention.

Carter has kicked more than his fair share of goals on Eden Park, but never quite like what he's preparing for at the moment - kicking for 24 hours on New Zealand's 'national stadium' to raise money for UNICEF.

"I don't really know what the strategy is," he says. "With my history of injuries in big moments, I might need a couple of guys backing up.

"I might have to give 'Beaver' a call just in case."

Of course, Carter is referring to the historic 2011 World Cup final victory over France at the same venue, when he was injured out of the tournament and Stephen 'Beaver' Donald was famously summoned from whitebait fishing to kick the winning goal.

The All Blacks hope they won't have to resort to anything similar to win another World Cup, but they already have their work cut out for them, as France's continued rise puts them firmly in the boxseat on home soil.

"Historically, when they're expected to win, the French tend to relax," says Carter. "But to build this consistency they have, they're going to be the favourites, in my opinion, for the World Cup."

That dominance hasn't gone unnoticed by the current All Blacks, who felt it firsthand at Paris last year, torn apart by a French side chasing history.

First-five Beauden Barrett thinks they can learn a lot from watching the Six Nations success.

"There's plenty of hype around them, so you want to be keeping an eye on them, and seeing how they're trending and progressing, and seeing what we're going to be up against."

The All Blacks will get their first crack at northern redemption against Ireland at home in July, a series Carter feels will offer a clear indication of how wide the margin is.

"The series against Ireland will be a huge test to see where we are," says Carter. "The Irish are performing extremely well and that's exactly the test we need."

The next 18 months are shaping as a crucial period for the All Blacks before their World Cup opener against France.