A leading figure in the Bougainville separatist movement says any effort to dissuade the people from seeking independence is too late.
Martin Miriori was speaking after revelations that former Papua New Guinea prime ministers Sir Rabbie Namaliu, Sir Julius Chan and Paias Wingti plan to visit Bougainville to try and ensure the country stays unified.
In June next year Bougainvilleans will vote on whether to become independent of PNG, as the final step in their region's lengthy Peace Agreement.
The former prime ministers have been encouraged by Prime Minister Peter O'Neill to urge Bougainvilleans to stay within PNG but Mr Miriori says they should have come earlier.
"That effort is too late, much too late. They should have come earlier. And some of these prime ministers that are trying to come - they are part and parcel of the problem."
Martin Miriori pointed out that Sir Rabbie Namaliu was responsible for escalating the Bougainville crisis by sending in the PNG Defence Force, while Sir Julius Chan tried to send the mercenary group, Sandline, into Bougainville.