He formed political party Young Malagasies Determined and was elected Mayor of Antananarivo in 2007. While in this position, he led an opposition movement against then-President Marc Ravalomanana that culminated in a 2009 political crisis. Rajoelina was appointed as President of the High Transitional Authority of Madagascar (HTA) by a military council, in a move characterised as a coup d'état by the international community. Rajoelina dissolved the Senate and National Assembly, and transferred their powers to a variety of new governance structures responsible for overseeing the transition toward a new constitutional authority. This conflicted with an internationally mediated process to establish a transitional government. Voters approved a new constitution in a controversial national referendum in November 2010, ushering in the Fourth Republic.