Naga insurgent group NSCN(IM) has threatened to break its 27-year-old ceasefire agreement with the government and return to its "armed struggle" if its demands for a separate "national flag and constitution" are not met.

The group, which carried out a violent insurgency in Nagaland soon after India's independence in 1947, entered into a ceasefire pact in 1997 before starting prolonged peace talks with the government's interlocutors.

On August 3, 2015, the NSCN(IM) signed a framework agreement with the government in presence of Prime Minister Narendra Modi to find a permanent solution.

In a statement released on Friday, general secretary of the group and chief political negotiator Thuingaleng Muivah said he and former chairman, late Isak Chishi Swu, went to the negotiating table for the resolution of the conflict through peaceful negotiation and also honouring the commitment of former prime ministers P V Narasimha Rao, H D Deve Gowda, Atal Bihari Vajpayee and others to resolve the issue through peaceful political negotiation, leaving aside armed movement.

Accordingly, the political negotiations began on August 1, 1997 and since then more than 600 rounds of talks had held without any pre-conditions both in India and abroad, leading to the signing of the framework agreement of August 3, 2015, he said.

Muivah alleged that authorities and the leadership in the government have "deliberately betrayed" the letter and spirit of the framework agreement by refusing to recognise and acknowledged the Naga "sovereignty national flag and sovereign national constitution".

He said the benchmark for a political agreeing between the government and the NSCN must be according to the letter and spirit of the framework agreement wherein among others, the Naga "sovereign national flag and Naga sovereign national constitution" must be an integral part of the political agreement.

Muivah said today or tomorrow, Naga's "unique history, sovereignty and freedom, sovereign territory, sovereign national flag and sovereign national constitution are non-negotiable".

"Nevertheless, even if the odds are against Nagas and the NSCN, we shall take whatever steps that is necessary according to the decision mandated by Nagas and the Naga people will protect and defend the Naga unique history, sovereignty and freedom, sovereign territory, sovereign national flag and sovereign national constitution, by whatever means including armed struggle," he said in the statement.

Officials said in New Delhi that the peace talks with the NSCN-IM is currently going nowhere as the group has been insisting for a separate Naga flag and constitution, a demand rejected by the central government.

Separately, the government is also holding peace parleys with splinter groups of the NSCN after entering into ceasefire agreements.

The groups which have entered into ceasefire agreements are: NSCN-NK, NSCN-R, NSCN K-Khango and NSCN-K-Niki.

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