Security measures have been beefed up around NSCN (IM) camp at Hebron, near Dimapur, where the two leaders -- chairman Issac Chisi Swu and general secretary Thuingaleng Muivah -- would be staying, official sources said.
Isak Swu and T Muivah had a one-hour meeting with the former prime minister at his residence.
The extension of the ceasefire is being seen as the only way to move towards a permanent solution to the Naga issue.
It is likely that the ceasefire announced by the government and the NSCN(K) will be extended for another year.
The Centre's special representative, K Padmanabhaiah, and IB chief K P Singh will leave on Tuesday for Amsterdam to hold parleys with the outfit's leaders.
The delegates made a declaration and handed over a copy of it to NSCN (I-M) chairman Isak Chishi Swu and its general secretary Th Muivah.
"All hurdles have been cleared by the Government of India before their visit and the collective leadership are arriving any time in the next few days," said NSCN-IM information and publicity in-charge Kraibo Chawang.
The Centre's interlocutor to hold talks with the Naga leaders,\n\nK Padmanabhaiah, arrived in New Delhi on Tuesday morning.\n\n
Nagaland Chief Minister Neiphiu Rio on Sunday said his government will continue to work for the withdrawal of the Armed Forces Special Powers Act from the state.
The prime minister assured the people of Nagaland that the Centre will always be sensitive to the needs of the people.
'Operation Hurricane' was in progress in state's Tirap district bordering Myanmar.
Isak Chishi Swu and T Muivah will represent the Naga outfit; the government side is likely to include Oscar Fernandes, Prithviraj Chauhan and S Reghupaty.
Swu and Muivah, who are scheduled to reach New Delhi on Sunday night from Amsterdam, are expected to meet Home Minister Shivraj Patil on Monday, official sources said.
They were last here about a year ago.
Let us end tensions that have sometimes existed between us and live as good neighbours, who respect each other's rights, the outfit said in a statement.
'The fact that NSCN leaders are here in India for talks is a very positive development,' says Mizoram Chief Minister Zoramthanga.
The Centre's interlocutor for the Naga peace process, K Padmanabhaiah, is holding talks with National Socialist Council of Nagalim (I-M) in Bangkok for the second time since the Manmohan Singh government took over.
The Goa chief minister said, "The surgical strikes against militants in PoK was planned 15 months in advance."
The talks should lead to an amicable settlement by establishment of a tripartite arrangement to accommodate Meitei, Naga and Kuki, the Kuki National Army said.
A joint statement signed by the two sides at the conclusion of their three-day talks said "both parties must work to maintain a peaceful and violence-free environment till then."
During its talks with the Centre, the NSCN (I-M) has demanded the formation of 'Greater Nagaland', which includes parts of Manipur.
Nagas have now a much better understanding with the people of India, NSCN (I-M) chairman Isak Chisi Swu said after meeting George Fernandes.