Nepalese lawmakers are meeting in the capital Kathmandu in an effort to avert a political crisis as the deadline for a new constitution looms.
The government and opposition Maoist party are debating whether to prolong the life of the current parliament, whose term expires on Friday.
The parliament was elected in 2008, following 10 years of civil war.
A new constitution to replace the interim one must be agreed, but there has been disagreement over its details.
The government wants parliament to be given at least another six months to write the constitution.
The Maoists says before that can happen the prime minister must resign in favour of a national unity government led by them.
They also want their former fighters to be integrated into the national army, but there is no consensus over how this should be done.
The BBC's Joanna Jolly in Kathmandu says that although the three main parties have been deep in negotiations for several weeks, no side appears willing to make the compromises needed to agree a deal.
On Thursday, the President of Nepal called the party leaders into a meeting and told them to resolve their differences before parliament is dissolved or the country faces the prospect of presidential rule or even emergency rule.
Maoist strikesMost of the MPs, including the Maoist party leader Pushpa Kamal Dahal also known as Prachanda, have arrived at the assembly hall to debate the government proposal to extend the assembly's term.
The proposal must be approved by two-thirds of the lawmakers but no single party has a majority in the assembly.
The Maoists, who ended their decade-old rebellion in 2006 and joined a peace process, are the largest party in parliament.
Both the assembly and Nepal's interim constitution will expire at midnight Friday.
Earlier this month, the Maoist party brought Nepal to a virtual standstill with a six-day strike in an attempt to force the government to resign.
Reference: BBC News
