A huge sperm whale has been torched and butchered after washing up on a beach in the Wairarapa.

John Key has called anti-whaling protester Pete Bethune "downright ungrateful" after he slammed the Government.

Pete Bethune says he fully supports Sea Shepherd, despite the organisation "booting him out" during his trial in Japan.

A deal negotiated with the Japanese resulted in a suspended sentence for anti-whaling activist Pete Bethune, but means he won't be on the next Sea Shepherd protest.

Reports say Pete Bethune's prosecution in Tokyo has demanded a two-year prison term.

The nations that make up the International Whaling Commission (IWC) meet next week to decide whether to allow whaling in Antarctic waters for the next decade.

Researchers estimate that the iron-rich faeces of sperm whales helps remove 400,000 tonnes of carbon from the atmosphere each year.

Yurika Arai explains the Japanese attitude to whale meat.

Conservationists want Australia to lead the anti-whaling charge at a major summit next week, in response to footage of a whale being hit by an exploding harpoon.

Japanese prosecutors are demanding two years jail for NZ anti-whaling activist Peter Bethune, on trial for assault and charges after the boarding of a harpoon ship in Antarctic waters.

Anti-whaling group Sea Shepherd banning NZ activist Pete Bethune has caused bemusement in Japan ahead of his last day of trial in Tokyo today.

Sea Shepherd banned Kiwi anti-whaling activist Pete Bethune from future protests in an effort to help him avoid jail time.

An embarrassed TVNZ has been forced to apologise to viewers after it was duped into broadcasting a live-to-air interview with a fake pro-whaling lobbyist.

Pete Bethune is axed from future Sea Shepherd anti-whaling protests for having a bow and arrows on board the sunken Ady Gil.

The state broadcaster has admitted it was duped by a prankster pretending to be a pro-whaling advocate.