NEW DELHI: Around 50 insurgents belonging to a breakaway faction of the Naga terror outfit NSCN(K) are likely to join the national mainstream as the group is finding it difficult to survive following enhanced cooperation between the Indian Army and the Myanmar's armed forces along the border, sources in the security establishment said on Saturday.

The faction led by Niki Sumi has decided to surrender as a result of combined efforts against it by the Army, state security forces and military intelligence in the last few months, they said, adding it will be a boost for the Naga peace process.

The overall coordination and cooperation between the Indian and Myanmar's armies on the management of the Indo-Myanmar border has improved following a recent visit to the neighbouring country by Chief of Army Staff Gen MM Naravane, they said.

"The diplomatic efforts in the military domain by the Chief of Army Staff during his recent visit to Myanmar have paid rich dividends," said an official on the condition of anonymity.

In October, Gen Naravane, accompanied by Foreign Secretary Harsh Vardhan Shringla, paid a crucial visit to Myanmar during which India decided to supply an attack submarine to the Myanmar Navy besides agreeing to further deepen overall military and defence ties.

Myanmar is one of India's strategic neighbours and shares a 1,640-kilometre-long border with a number of north-eastern states including militancy-hit Nagaland and Manipur.

The NSCN (Khaplang) and several other Naga terror groups have been demanding the establishment of a 'Greater Nagaland' comprising all the Naga-inhabited areas of neighbouring Assam, Manipur and Arunachal Pradesh.

The sources said Starson Lamkang, a key leader of the breakaway faction, along with 52 cadres are currently in the process of surrendering to the security forces in Phek district of Nagaland.

They said eight more cadres of the group are also likely to surrender taking the total to around 60.

The group led by Niki Sumi had broken away from the NSCN (K-Yung Aung). The total strength of the Niki faction appears to be 60-65 terrorists and its cadres decided to surrender as surviving in Myanmar became very difficult for them, the sources said.

Sumi is an insurgent leader from the Sema tribe and belongs to Zunebhuto district of Nagaland, the sources said, adding he was a prominent "commander" in NSCN (K) group.

He is also a key accused in the attack on an Army convoy in Manipur's Chandel district in June 2015 by the NSCN(K) in which 18 army personnel lost their lives. He carries a reward of Rs 10 lakh.

Days after the attack, the Indian Army had carried out an operation in areas near the Indo-Myanmar against the NSCN(K) terrorists.

India has been concerned over some terror groups from the Northeast region taking shelter in Myanmar. The country has been assuring India that it would not allow any insurgent group to use its territory against India.

Various Naga terror groups are currently holding talks with the Centre to resolve the decades-old Naga issue.