New Zealand's foreign minister says his country recognises West Papua as a part of Indonesia.
Vanuatu's Daily Post newspaper reports Winston Peters made the remark during his recent visit to the country.
Vanuatu's government is seeking regional support to have West Papua, the Indonesian provinces of Papua and West Papua, inscribed on the UN decolonisation list next year.
The Charlot Salwai-led government plans to submit a draft resolution on the matter at the Pacific Islands Forum leaders summit in Nauru next week.
However, forum members such as Australia, Papua New Guinea and Fiji have voiced opposition to the move.
Speaking in Port Vila, Mr Peters implored Vanuatu to see PNG's position as the direct neighbour of West Papua.
He said without underestimating the emotional sincerity of the Vanuatu people's feeling on the issue, they couldn't overlook how deeply concerning this issue is to the nearest neighbour.
Mr Peters said the "Indonesian government should be worked with to look at its programmes of improving the lives of its people".
But he said even PNG would agree that economic and social conditions of West Papua per capita were higher than PNG's.