Veteran leader and chief of NDPP Neiphiu Rio on Thursday took oath as the new chief minister of Nagaland along with 11 ministers.

The oath of office and secrecy was administered to Rio by Governor PB Acharya in a special ceremony in Kohima.

Rio will have to prove his majority on the floor of the house on or before March 16.

The attendees at the oath-taking ceremony in Kohima included defence minister Niramala Sitharaman, minister of state (home) Kiren Rijiju, BJP president Amit Shah, BJP national general secretary Ram Madhav.

Prime Minister Narendra Modi had expressed his inability to attend the event, a source in the Raj Bhavan had said on Wednesday.

The development comes after the Nationalist Democratic Progressive Party (NDPP), which forged a pre-poll alliance with the Bharatiya Janata Party (BJP), unanimously elected Rio as its Legislature Party leader.

In the recently concluded Assembly elections, the ruling NPF won 26 seats. The NDPP-BJP alliance cornered 30 seats and has the support of two NPP MLAs, one JD(U) MLA and an Independent.

Outgoing Chief Minister TR Zeliang had on Tuesday submitted his resignation which the governor accepted and asked him to continue in office till an alternative arrangement was made.

Rio has served as the state’s CM three times before this, between 2003 and 2014.