Former Maoist guerrilla Sukh Bahadur Roka Magar spent his youth fighting for greater equality in his native Nepal, a goal he had hoped to see enshrined in a new constitution that was voted into law this week.

But the 47-year-old farmer says the long-delayed bill, aimed at cementing the Himalayan nation's transformation from feudal Hindu monarchy to secular democratic state, has left the revolution he fought unfinished.

"Thousands of lives were lost during the conflict for the sake of a new constitution that could guarantee people's rights," he said.

"The monarchy has gone, but power has not yet shifted to ordinary people.

"I had a different vision of the new Nepal. But many compromises have been made."

The new constitution endorsed in parliament this week is the first to be drawn up by elected representatives of Nepal's people after centuries of autocratic rule.

It is the final stage in a peace process that began when the Maoists laid down their arms in 2006 after a decade-long civil war with state forces and turned to politics, winning parliamentary elections two years later and abolishing the monarchy.

Work on the bill began in 2008 and was initially supposed to finish by 2010, but the Maoists were unable to secure enough support for the two-thirds majority needed to push it through parliament.

After years of disagreement, the three biggest parties finally reached agreement in June, spurred by a 7.8-magnitude earthquake two months earlier that killed nearly 8,900 people and destroyed around half a million homes.

They agreed to divide the country of 28 million people into seven federal provinces, a move aimed at devolving power from the centre.

But before voting even began, violent protests broke out over the proposed borders, which historically marginalised groups including the Madhesi and Tharu ethnic minorities say will leave them under-represented in the national parliament.

More than 40 people have been killed in over a month of clashes between protestors and police, among them two young children and a police officer lynched as he was driven to hospital in an ambulance.

It was some of the worst violence Nepal has seen since the end of the conflict nine years ago and prompted neighbouring India to issue a statement expressing concern and urging "flexibility on the part of all the political forces", even as voting on the draft was under way.

- 'Flawed, but not fatally' -

A clause that will make it more difficult for women to pass their citizenship onto their children has also attracted fierce criticism, with rights activists calling it a backwards step.

Journalist and political commentator Kunda Dixit said the three main parties had "tried to bulldoze a formula that serves their own immediate political interests rather than have an inclusive, sustainable solution that can bring stability to the country".

But in a blog posted as the voting drew to an end on Wednesday, he said the controversial bill was "flawed, but not fatally so", and was flexible enough to be improved.

Bhimarjun Acharya, a constitutional lawyer, said the bill included provisions for improving the involvement of low-caste groups, women and minorities in national politics, although he said some of these were not clear-cut and success would depend on how they were implemented.

Political leaders had argued that passing a constitution -- even an imperfect one -- was preferable to the continuation of the political limbo that some say has held up crucial quake aid.

This week, parliament finally passed a bill formally establishing a National Reconstruction Authority that was set up to oversee rebuilding after the April quake, but had been unable to start work until its status had been enshrined in law.

The new constitution will come into force after a ceremony on Sunday evening and will trigger the resignations of both the government and the president, although the timing of those changes is unclear.

Maoist leader Pushpa Kamal Dahal, better known by his nom de guerre Prachanda, or the fierce one, hailed it as a "victory of the dreams of the thousands of martyrs and disappeared fighters".

Magar, the former rebel who fought under Dahal's command, was not so sure.

"We need to raise our voices until Dalits, women and indigenous people are empowered," he told AFP.

"Only then will I believe that the goals of 10 years of civil war have been achieved."