West Papua advocacy groups based in Australia and New Zealand have urged the Pacific Islands Forum to act decisively on Papua.
Representatives of the Forum's 18 members are gathering for their annual leaders summit in Apia this week.
Two years ago Forum leaders agreed to send a fact finding mission to Papua to investigate ongoing allegations of human rights abuses by Indonesian security forces.
Indonesia's government, however, has not agreed to a mission.
Both the Australia West Papua Association and New Zealand's West Papua Action Auckland group want the Forum to press Jakarta more on the matter.
The two groups cite recent moves by seven Pacific Island nations to raise the issue of human rights in West Papua at the UN General Assembly and UN Human Rights Council.
Vanuatu, Nauru, Tonga, Solomon Islands, Tuvalu, the Marshall Islands and Palau have called for the UN to take account of the evidence of widespread human rights violations and conduct a systematic investigation with recommendations for actions.
The two advocacy groups have called on the Forum to support the seven Pacific nations call at the UN to investigate and report on the alleged human rights abuses in West Papua.
The Forum, they said, should establish a regional Fact Finding Team to conduct a Human Rights Assessment in West Papua.
In its open letter to Forum leaders, the Association said it was encouraged that the leaders previously agreed the issue of West Papua should remain on their agenda. But it suggested the issue should not be left to drift just because Jakarta was unhappy about the idea of a fact-finding mission.
"The Indonesian President has said that West Papua is now open and the authorities are saying that the human rights situation is improving. If this is the case why not allow a PIF fact-finding mission to the territory?" said the open letter.
There was also a call for the re-inscription of West Papua with the UN Committee on Decolonisation.
"The Special Committee on decolonization visited New Caledonia in March 2014 and AWPA urges the PIF leaders to ask the Committee to also visit West Papua on a fact finding mission to investigate how the West Papuan people have fared under Indonesian rule," said the Association.
West Papua Action Auckland said that the Forum had "turned away from addressing self-determination for West Papua, despite the fact that the people of West Papua were denied any say in the matter when Indonesia took over the territory in the 1960s".
The issue of West Papua was raised in Port Vila in July at the 14th Pacific Regional Meeting of the African Carribean and Pacific Group's Joint Parliamentary Assembly with the European Union.
As host, Vanuatu introduced the item on West Papua, which was supported by Kiribati, Marshall Islands, Nauru, Samoa, Tonga, and, "on purely humanitarian grounds", by Papua New Guinea.
The communiqué stated that "members called for the immediate halt to the brutal and senseless killings of the indigenous people of West Papua and referred the matter to the next JPA meetings".
Meanwhile, both Papua advocacy groups urged Forum leaders to give West Papua official status within the organisation, saying there were already many non-self governing territories and organisations that have this.
"The Forum should grant observer or associate status to the representatives of the West Papuan people, the United Liberation Movement for West Papua," said West Papua Action Auckland.
"This would put the Forum in a strong position to mediate dialogue between the ULMWP and Jakarta."