The involvement in the government by King Tupou VI is a return to the "dark ages" for the Kingdom, a long time campaigner for democracy in Tonga says.
The King last month withdrew his support for the Ministers holding two portfolios.
Tonga's Prime Minister Hu'akavameiliku Siaosi Sovaleni has reportedly stepped down from his defence portfolio, with Foreign Affairs Minister Fekita 'Utoikamanu reportedly doing the same.
Sources in Nuku'alofa have told RNZ Pacific the decision to resign comes following a meeting between Hu'akavameiliku and a Cabinet team held with King Tupou VI earlier this month.
Kalafi Moala said the King's decision to withdraw support is a retrograde step.
"The reform in 2010 was that he [the King] would get out of trying to run the government or to appoint government," he said.
"And with this King, to me, this is a very very bad move, and there is a lot of public unhappiness about it."
Hu'akavameiliku has reportedly sent a proposal to the King, recommending that Crown Prince Tupouto'a 'Ulukalala, a senior official at the Ministry of Foreign Affairs, be appointed Minister of Defence and Foreign Affairs.
An official announcement is expected to be made after a Privy Council meeting that will be chaired by the King on Thursday.