Fiji has attacked Australia's new hardline asylum seeker policy, warning it could alter the social fabric of the Pacific islands.

Fiji Foreign Minister Ratu Inoke Kubuabola on Monday launched an acidic broadside against the government's plan to send all asylum seekers coming by boat to Papua New Guinea for processing and possible resettlement.

He says Australia used its economic muscle to persuade a Melanesian country to accept thousands of people who are not Pacific Islanders into the region.

"For an Australian problem, you have proposed a Melanesian solution that threatens to destabilise the already delicate social and economic balances in our societies," Mr Kubuabola told the 20th Australia-Fiji Business Forum in Brisbane.

"This deal, and those mooted with Solomon Islands and Vanuatu, clearly threatens our interests by altering the fundamental social fabric of any member country that accepts a deal.