Madagascar's military ruler Col Michael Randrianirina has dissolved the government unexpectedly, dismissing the prime minister and the entire cabinet, according to a statement from his spokesperson.

"The government has ceased its functions" it said, adding that Randrianirina will appoint a new prime minister "in line with the provisions stipulated by the constitution".

No reason was given for the move.

Randrianirina seized power last October from Andry Rajoelina, following weeks of youth-led protests on the Indian Ocean island. Rajoelina had been elected president for a third term in a disputed poll in 2023.

The demonstrations were over persistent power and water shortages, culminating in the army siding with the demonstrators.

Randrianirina has pledged to call new elections within two years.

Last December, the regional bloc, the Southern African Development Community (Sadc), directed Madagascar's military authorities to submit a roadmap for restoring democracy including plans for fresh elections by the end of February.

But in a surprise on Monday, Randrianirina sacked his entire government and assigned permanent secretaries to run ministries' day-to-day operations until a new cabinet is formed.

Randrianirina has not explained the motivation for the mass sackings, but leaders of the Gen Z movement, whose grassroots mobilisation helped bring the military leader to power, have called for more inclusiveness in the transition process and greater representation in decision-making structures.

Activist groups, calling themselves Gen Z and Gen Y movements, had recently issued a 72-hour ultimatum for Randrianirina's resignation, citing frustration with his performance, local media reported.

Businessman Herintsalama Rajaonarivelo had been appointed prime minister in October in an effort to bridge the divide between military leadership and civilian government.

The the Gen Z movement leaders rejected his appointment at the time, saying it was made in a "non-transparent" manner and "without consultation".

The group demanded to know how Rajaonarivelo was selected given what it said were his connection to the previous government.

They then said that the decision "runs contrary to the desired structural change" the movement was seeking.

Monday's dissolution of the government could mark a significant shift in the country's political landscape with the military leader seeking to establish a new administration.