Nauru defended its support for commercial whaling Tuesday after critics suggested that Japan had bought the tiny Pacific nation's vote with promises of increased aid.

The aid-dependent nation joined the International Whaling Commissionahead of its meeting last week at Ulsan in South Korea and supported an unsuccessful Japanese move to resume commercial whaling.

Nauru's ambassador to the United Nations Marlene Moses said her country's stance was determined by the government on the merits of the issue, not by outside factors.

"Nauru voted openly at the meeting, and we stand by our vote," Moses said in a statement issued by Nauru's Melbourne-based public affairs office.

"Foreign governments have an obligation to respect our national decisions and not to undermine our sovereignty by suggesting that our participation in the IWC was motivated by anything other than securing the best outcome for our people."

Moses said suggestions Nauru was swayed by Japanese influence were unfair and the government had decided its position on the merits of the whaling issue.

"Some whale species have the potential to devastate our tuna stocks, and, as a country whose food security and economy relies heavily on fishing, it is our responsibility to ensure the sustainability of our people's livelihoods." she said.

Australia, a leading opponent of Japan's pro-whaling push, has described Nauru's sudden interest in the whaling issue as "suspicious" but said the issue will not affect Canberra's role as the largest aid donor to the debt-crippled Pacific island.

"I don't think we want to go down the Japanese path and link that assistance to how people vote at international forums," Environment Minister Ian Campbell said while at the IWC meeting.

Australia was also angered that another Pacific nation, the Solomon Islands, supported whaling, despite assurances from its Prime Minister Allan Kemakeza that it would not back the Japanese push.