The leader of the Tonga Democratic Party says the government is manipulating state media to deny his party access.
This comes amid further delays in the Democrats' efforts to hold a vote of no confidence in the administration of Lord Tu'ivakano.
Parliament has been adjourned until Monday when petitions from public groups opposed to the motion will be heard.
One of the petitions criticises the Democrats for trying to unseat the government without explaining why, but Mr Pohiva says his party has not been given any opportunity to put its case on local state television and radio.
He says it is like being in a police state.
"A good example is Radio Tonga and Television Tonga are being used by government to support the reaction or opposition from government. We representatives of the people are not given a chance to present or to challenge motions and also petitions launched by ministers and also some of the nobles."
Radio Tonga has denied the claims