Australia is to argue Japan's whaling activities have breached international obligations.

A decision to kill 48 pilot whales found stranded on Stewart Island had been difficult but there was no alternative, DoC says.

Foreign Minister Murray McCully says he welcomes today's announcement by the Japanese Government that its whaling fleet will stop whaling in the Southern Ocean and return home.

Activists tailing a Japanese whaling ship say it has turned around and is on course for Japan.

Anti-whaling activists say reports of Japan's annual Southern Ocean whale hunt being suspended are a bluff.

About 70 pilot whales which became stranded at the top of the South Island have made it to deeper water.

A group of pilot whales appears to have beached once more on Farewell Spit, at the top of the South Island.

A pod of 66 pilot whales beached west of Nelson yesterday swam off on the high tide overnight, DOC says.

DOC staff have killed 10 pilot whales which survived the stranding of a pod of 24 in Parengarenga harbour in the Far North.

"It was cool. It turned on its side and just sat there looking at us just under the water."

Four whales stranded at Port Waikato yesterday are to be buried in sand dunes just metres from where they lay.

Anti-whaling activists are promising more attacks after throwing smoke grenades and "flash bangs" at Japanese whalers in the Southern Ocean today.

Anti-whaling activists in the Southern Ocean say they have located the Japanese whaling fleet and have already clashed with the whalers.