The United Liberation Movement for West Papua is calling for Pacific regional groups to investigate the alleged use of chemical weapons in Indonesia's Papua region.
The movement's chair, Benny Wenda, said the Pacific Islands Forum and the Melanesian Spearhead Group should urgently send fact-finding missions to Nduga regency.
This comes after unverified reports of the suspected use of white phosphorus weapons by Indonesia's military against civilians in Nduga.
Indonesia last month called the claims "totally baseless".
But Mr Wenda said its security operations in Nduga had created a "humanitarian crisis".
In a statement, he said Indonesia should also grant the UN High Commissioner for Human Rights access to West Papua to complete its own fact-finding mission.
Mr Wenda said humanitarian aid organisations should also be allowed in to Nduga to "relieve the suffering of West Papuans".
A massive joint police and military operation has been underway in the remote Highlands regency, as well as neighbouring regencies, since December, in a hunt for members of the West Papua Liberation Army.
The armed group is responsible for the killings of at least 16 Indonesian construction workers and one soldier in November.
The joint operation has sparked sporadic shootouts between the Liberation Army and Indonesia's military, with at least one soldier and one rebel fighter shot dead this year.