The Papua New Guinea prime minister, Peter O'Neill, says an independence referendum in Bougainville will not go ahead if key conditions are not met.
The vote is scheduled to be held on June 15 in 2019.
It is the final stage of the Peace Agreement between Port Moresby and Bougainville signed in 2001 to mark the end of a bitter civil war.
The ABC reports the prime minister telling parliament Bougainville needs to meet certain criteria before the vote can happen.
He said this includes the proper establishment of the rule of law, a proper government structure on Bougainville and the disposal of illegal weapons.
Mr O'Neill said all of these conditions are yet to be met.
The prime minister told parliament that the government needs to work harder to attend to these issues.
But Bougainville's president, John Momis, said the critical factor in the region's struggle since autonomy had been Port Moresby withholding funding that's guaranteed under the Peace Agreement and the constitution.