Ex- head of state Andry Rajoelina, removed from power by a military takeover the prior week, has lost of his citizenship under the new government.
The decree, signed by new Prime Minister Rajaonarivelo, referenced local laws stating that people who obtained overseas status would forfeit their Malagasy nationality.
He, 51, secured nationality of France in the past, resulting in appeals for his removal from the recent presidential race. However, he resisted such appeals and went on to win.
Rajoelina escaped the island country after extended demonstrations over ongoing utility failures, ending with a military takeover led by Col Michael Randrianirina.
Rajoelina has said he has gone into hiding for his protection, and his current position are unknown.
When he disclosed his citizenship in France ahead of Madagascar's last presidential election, he stated he had only secretly acquired it to make things easier for his offspring attending school in overseas.
In recent weeks, he had experienced demonstrations initially organised by youth group young protesters and influenced by similar demonstrations against authorities in Nepal, which were further aggravated when his administration reacted with force.
The president dismissed his power minister and then his government - but this failed to stop the calls for him to leave office.
Protesters had hoped that he would leave his post to create the path for a orderly, democratic transition.
However, he held onto authority, eventually leading to the nation's special forces, of which the colonel commanded, to assume authority.
The colonel was inaugurated and has established a fresh administration, vowing to hold elections within two years.
