New Zealand's prime minister, Helen Clark, says donor countries must work closely with authorities in Papua New Guinea to stop the spread of HIV/Aids.
Ms Clark has met people living with HIV and AIDS at a support centre in Port Moresby.
She says the trajectory the AIDS epidemic is on in Papua New Guinea is very similar to that which went on in Africa.
Ms Clark said that led to a huge lowering in life expectancy and a human tragedy that impacts across the economy and society.
HIV/Aids will be on the agenda for discussion during the forum, which is expected to endorse the 10-year regional cooperation programme known as the Pacific Plan.