The president of the Papua New Guinea autonomous province of Bougainville, Joseph Kabui, has not been invited to the special Melanesian Spearhead Group meeting currently being held in Vanuatu.
This is despite the meeting being called to discuss, among other things, the ongoing presence of former Fijian soldiers on Bougainville.
A former deputy to Mr Kabui, James Tanis, says there's mounting frustration on the ground that the situation isn't resolved.
And, he says there should be a Bougainvillean presence at the MSG meeting.
"It is important that the governments in the Melanesian Spearhead Group meeting get a first hand briefing from the ground situation from those who are on the ground. We have an autonomous arrangement where the autonomous government is responsible for implementing the peace agreement. And, what is needed is assistance from the government of Papua New Guinea."
Mr Tanis says the lack of assistance has led to shortfalls in what the autonomous Bougainvillean government can deliver, leaving people frustrated.
And, he believes this is playing into the hands of the mercenaries who are recruiting disaffected youth.
