The Radio Fréquence Plus Madagascar was founded by Ntsay and he served as its first president from 1992 to 2001. He was the general manager of the SOLIMA oil company in Madagascar from 1993 to 1997. From 1998 to 2007, Ntsay was a consultant for the
World Bank,
European Union,
International Trade Centre,
United Nations Development Programme, and
United Nations Population Fund. He was the Minister of Tourism from 2002 to 2003. Ntasy was Madagascar's representative to the
International Labour Organization from 2008 to 4 June 2018. Prime Minister
Olivier Mahafaly Solonandrasana resigned on 4 June 2018. President
Hery Rajaonarimampianina appointed Ntsay to replace Solonandrasana as prime minister. Ntsay was acting president in charge of a national unity government before the
2023 presidential election. 11 of the 13 presidential candidates accused Ntsay, who was aligned with
Andry Rajoelina, of performing an institutional coup. As a result of
widespread protests against water and power cuts in September 2025, Rajoelina announced that Ntsay's government would be terminated on 29 September 2025. Rajoelina maintained Ntsay's government in a caretaker role until a new Prime Minister was appointed, for which he assigned three days for selection. Amid the
2025 Malagasy coup d'état on 12 October 2025, Ntsay went to Mauritius aboard a private flight along with one of Rajoelina's advisers,
Mamy Ravatomanga. ==Personal life==