Transparency International Papua New Guinea says it is incorrect for MPs to claim they have the right to extend the parliamentary term.
Its spokesperson Lawrence Stephens says the latest such claims, made in advertisements placed by the Speaker Jeffrey Nape, are a gross abuse of the constitution.
He says MPs are deliberately misinterpreting a provision that allows parliament to order an early election, but makes no allowance for any extension of the term beyond five years.
Mr Stephens says there is widespread public anger at the moves by the politicians, especially since any perceived lack of preparedness at the Electoral Commission can be sheeted home to a lack of government funding.
"People suspect that we have a group of individuals who have simply decided the rules don't apply to them and they intend to stay in office at their pleasure, not the pleasure of the voters of Papua New Guinea."
Transparency International PNG's Lawrence Stephens.