India's government has signed a historic peace treaty with the leader of a key rebel group in India's insurgency-wracked northeast.

Prime Minister Narendra Modi signed the accord in New Delhi on Monday with Thuingaleng Muivah, the leader of the Isak-Muivah faction of the National Socialist Council of Nagaland. It ends a rebellion that festered in India's Nagaland and Manipur states for more than six decades.

The two leaders gave no specific details about the accord.

The rebel group was fighting for an independent homeland for the Naga tribes. It is the oldest and strongest of the nearly 30-odd rebel armies operating in the northeast since India's independence in 1947.

The group entered a cease-fire in 1997 but in nearly 18 years no formal peace deal could be agreed upon.