Tonga's leading pro-democracy advocate, MP Akilisi Pohiva, says he is hopeful deliberations by the constitutional change commission will begin later this week.
The government announced plans to set up the political reform commission nearly four months ago but little has happened to date.
Mr Pohiva says the members of the commission have been selected and are waiting for the King, who has been out of the country and is due to return this week, to swear them in.
Mr Pohiva says the pro-democracy movement has been doubting the government's commitment to the commission but it has received an assurance last week from the Prime Minister Dr Feleti Sevele.
"At this point of time we expect the Prime Minister and Government to come forward and honour the commitment. There was a heated discussion in our last session, last week, and he made a statement to the members saying, don't worry, Government is already committed to start the work of the commission when His Majesty arrives."