Acharya, in a letter to Rio, asked him to prove his majority on the floor of the House on or before March 16, the source said.
The governor said he had received letters of support in Rio's favour from 12 legislators of the Bharatiya Janata Party, one letter from the Janata Dal-United and another from an Independent MLA, besides the 18 legislatures of the NDPP.
The new ministry will be sworn in on March 8, the source said.
Union minister Jagat Prakash Nadda, along with BJP general secretary Arun Singh and state BJP president BJP Visasolie Lhoungu, met the governor earlier on Tuesday and submitted a letter of support to Rio with the signatures of all 12 BJP MLAs.
The BJP leaders informed the governor that Y Patton had been elected the BJP Legislature Party leader in the Assembly.
National People's Party's state president Ato Yepthomi said he had also submitted a letter supporting Rio to the governor.
The governor has asked him to give a letter of support signed by the party's national president Conrad Sangma along with a letter with the signatures of both the NPP MLAs at the earliest.
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 T R Zeliang on Tuesday submitted his resignation which the governor accepted and asked him to continue in office till an alternative arrangement was made.
Earlier in the day, officials from the Election Commission along with state Chief Electoral Officer Abhijit Sinha submitted a notification constituting the 13th Nagaland legislative assembly to the governor.
The governor dissolved the 12th Nagaland Legislative Assembly, the source said.
IMAGE: Nationalist Democratic Progressive Party leader Neiphiu Rio, with BJP general secretary Ram Madhav and others, meets Governor of Nagaland P B Acharya at Raj Bhavan, in Kohima on Sunday. Photograph: PTI Photo
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