Girija Prasad Koirala, Nepal's prime minister, and other party leaders formally met rebel chief Prachanda and senior aides on Sunday for the first time in nearly four months after the Maoist leader threatened to start street protests if the talks were further delayed.
Officials said the meeting, taking place in Koirala's high-security official residence in Kathmandu, was expected to continue for a few days.
Outside the venue, about two dozen people held placards reading "Dissolve parliament, create an interim legislature" and "Beware of foreign interference."
Koirala said on Friday: "We need patience. Everything will be positive and we will try to find a solution to all problems."
King Gyanendra restored democracy after mass protests in April.
In June, Nepal's interim government and the Maoists, who have attempted to topple the monarchy, struck a power-sharing deal envisaging an interim constitution, a temporary parliament and an interim cabinet including rebel participation within a month.
But none of these measures has yet been implemented.
The interim government, which the Maoists are expected to join, is to supervise elections to a special assembly to draw up a new constitution, a main rebel condition to end their revolt.
Prachanda said on Friday: "The government is wavering in implementing the deal. It is trying to avoid progressive change in the country."
The Maoists have been fighting since 1996 to turn the Himalayan nation into a communist republic, a conflict in which more than 13,000 people have been killed.
They now say they will accept the outcome of the assembly vote.