Congress president Sonia Gandhi met leaders of the National Socialist Council of Nagalim (Isak-Muivah) in New Delhi on Monday.
However, the formal dialogue between the Centre and chairman Isak Chisi Swu and general secretary Thuingaleng Muivah, which was to begin on Monday, was postponed by a day.
"We are all for long-lasting peace but the solution should not create further problems," Congress sources quoted Gandhi as having told Isak and Muivah.
The discussions assume significance as Nagaland is a Congress-ruled state whose Chief Minister S C Jamir has welcomed the peace process, but asked the Centre to talk to all factions of the underground movement.
The Congress chief also met an all-party delegation from Manipur, led by Chief Minister Okram Ibobi Singh. The delegation wanted to elicit her views on preserving the territorial integrity of Manipur in the backdrop of the Naga peace talks.
The delegation had earlier called on former prime minister H D Deve Gowda and Communist Party of India-Marxist leader Sitaram Yechury.