Papua New Guinea's shadow justice minister Kerenga Kua says MPs must put more effort into grappling with implications of the Bougainville referendum.
Bougainville is to hold a vote this year on whether to retain its autonomy status or become fully independent.
After the vote the PNG national parliament will then have the final say on the matter.
But Mr Kua said there had not been enough work done to make both the people of Bougainville and the MPs aware of the significance of the national parliament's role.
"The parliamentarians in Port Moresby, they need to understand that they have such a very serious responsibility on their hands as a matter of law, and they must now be investing a lot of time and effort into trying to understand how they are going to grapple with this issue when it lands on their laps after the referendum has been concluded and the outcome is that there shall be independence for the people of Bougainville."