The new 303-seat parliament, with 83 former rebel members, was due to be sworn in and meet for the first time later Monday, nearly nine months after the Maoists and the government reached a ceasefire deal.

Parliament's unanimous vote in favour of the constitution was hailed by a minister in the alliance that has governed since King Gyanendra abandoned direct rule in April 2006.

"The interim constitution will be in favour of the people of Nepal and has mentioned that executive power ultimately rests with the people," said Narendra Bikram Nemwang, the law minister, who spoke on behalf of elderly Prime Minister Girija Prasad Koirala, who was not present at Monday's session.

Among the Maoist delegates slated to join the new parliament are members of marginalised groups, such as lower castes never before represented in Hindu-majority Nepal's parliament.

The Maoists were to join the cabinet within a couple of weeks, after negotiations on which posts they will hold.

The rebels launched a deadly "people's war" in 1996 to install a communist republic in the impoverished Himalayan nation. The conflict claimed at least 12,500 lives and laid waste to Nepal's already fragile economy.

The new temporary constitution includes provisions that formally strip Gyanendra of his status as head of state, including control of the army, with his executive powers passing to Koirala.

The new parliament will oversee elections expected in June 2007 to a body that will draft a new permanent constitution and tackle the controversial issue of the monarchy's fate.

"The house has made historic decisions which will be written in golden letters in Nepali history," leader of the Communist Party of Nepal (United Marxist Leninist) Madhav Kumar Nepal told a television station from parliament on Monday.

The vice president of the Nepali Congress Party, Nepal's largest, told parliamentarians the new constitution and parliament would turn a page in Nepali history.

"The promulgation of the interim constitution will be a revolutionary step in establishing a new Nepal. Now, Nepal will witness lasting peace and security," said Sushil Koirala.

Some politicians, however, had earlier called for the interim document to be amended.

"There are still some faults in the interim constitution. It has not addressed the sentiments of the public as expressed during the April 'people's movement'," said Bharat Mohan Adhikary, a leader from the CPN (UML).

Rebel spokesman Krishna Bahadur Mahara told AFP the Maoists were "excited and looking forward to being part of the interim legislature".

The Maoists and seven parties in government struck a loose alliance in November 2005, after King Gyanendra seized direct control of the state earlier that year.

The king restored parliament in April last year, after weeks of mass protests forced him to end direct rule.

The rebels and parties agreed last year to place their weapons and combatants under UN monitoring, with the first arms to be deposited on Monday.

The rebels want Nepal to become a republic, but other parties in government prefer a ceremonial monarchy.