Nepal's political process has been in deep freeze since May when the last Assembly was dissolved by the High Court because it couldn't agree a constitution and a new government structure.
The dissolution ended four years of political intrigue and wrangling by Assembly members.
Nepal's last Assembly emerged as part of a peace agreement that ended a civil war between Maoist rebels and monarchists in 2006.
Around 15,000 people were killed and up to 150,000 people displaced during the decade-long civil war in which the Maoist's Communist Party of Nepal wanted to overthrow the monarchy and set up a republic.
But in 2006 the Maoists joined other political parties in a peace accord, monitored by the United Nations, in an effort to create a more democratic government for the isolated Himalayan Mountain country with India to the south and China to the north.
The Maoists placed their weapons under U.N. control and the monarchy was abolished in 2008.
However, they have sought assurances from the government and other political parties that most of their former fighters, many still waiting in holding camps in remote areas, will be inducted into the regular army.
The issue of how many are eligible and when they should be inducted has remained one of the stumbling blocks for an agreement over a new constitution.
Bhattarai said he had "no intention to stick to power" after a new constitution was agreed, a report by the Himalayan Times newspaper said.
But he said a new constitution and government structure should ensure the rights of "the oppressed class, caste, region, gender and communities."
Bhattarai said the last Assembly was dissolved because some parties rejected identity-based federalism which would protect people's rights.
He was speaking at a conference in Kathmandu organized by the Nepal Federation of Indigenous Nationalities, the Himalayan Times reported.
An estimated 19,000 registered former Maoist fighters are waiting in remote base camps, a report by the on-line newspaper eKantipur.com has said.
While the Nepalese wait to see what form of government they will get, former king Gyanendra Shah, 64, hinted last month he is open for a return of the monarchy.
"To save our nation at these difficult times, a new power should rise. This power could be anything from the previous monarchy to something different," he told news Web site Nepal24.
"The people are looking for our role now, they just need to be little patient and soon they'll know about our role."
He didn't make clear if he envisaged a ceremonial role for the monarchy or more active political engagement.