The New Zealand prime minister, Helen Clark, has failed to get any concessions from Japan on its whaling program during her visit to Tokyo.

But she has won agreement to study the benefits of a trade deal between the two countries.

The Pacific News Service reports Ms Clark told her Japanese counterpart, Yasuo Fukuda, she opposes Japan's whaling program in the Southern Ocean - a program also vigorously opposed by Australia.

She also had a longer and more detailed discussion on the issue with Japan's chief cabinet secretary, expressing New Zealand's opposition to both the killing of whales and the sale of their meat.

Produced by Radio Australia and Australia Network