New Zealand have decided to adopt a more aggressive pre-match Haka before each of their World Cup matches.

The new, improved haka is figuring prominently in New Zealand's World Cup preparations and will debut when the All Blacks kick off their campaign against Tonga at Bristol on Sunday.

The new version of the famous Maori dance will feature more aggressive actions to accompany the cry of `Ka Mate, Ka Mate, Ka Ora, Ka Ora' at the start of each game from the All Blacks. Captain Taine Randell shed light on the thinking behind the new choreography which will feature the beating of chests rather than slapping of thighs at crucial moments and an altogether more involved performance from all concerned.

"They are stronger actions and more appropriate to what the All Blacks are trying to do," Randell said.

Tonga, though, have their own battle cry of `Ikale Tahi' to boost them against a New Zealand side they believe could have its mind on other matters.

"The All Blacks will be looking ahead to their game against England, while we're totally focused on beating them on Sunday," said Tongan coaching director Dave Waterston.