Nepal has plunged deeper into crisis after feuding politicians, throwing microphones and shoes, failed to meet a deadline to table a new constitution, seen as a key step to stability in the Himalayan state.

Parliament Speaker, Subash Nembang, was forced to adjourn a late-night session of parliament on Thursday, after scuffles between opposition politicians brought a halt to proceedings.

Opposition politicians threw microphones and shoes at each other, after the Maoist-led opposition stormed the well of the main chamber. Three security marshals were reportedly injured in the scuffles.

"If political parties are not able to fulfil the commitment they made to the people...they will never trust us," Nembang told the squabbling politicians.

Authorities were forced to deploy 1,000 police to guard parliament after the violence spilled onto the streets, with 2,000 flag-waving protesters demonstrating outside.

Nepal's rival parties have spent years mired in deadlock while trying to reach agreement on a national constitution.

The ruling alliance, led by the Nepali Congress, had hoped to develop a new constitution, but protests by the main opposition Maoist party meant a self-imposed deadline was missed.

A new constitution is widely seen as crucial to ending the instability that has plagued Nepal since the end of a civil war in 2006, when Maoist guerrillas entered politics, ending a decade-long insurgency that left an estimated 16,000 people dead.

Six prime ministers and two elections later, discord between the opposition Maoists and ruling parties has intensified, paralysing the drafting process.

Landlocked Nepal has been in political limbo since 2008, when it's 239-year-old monarchy was abolished. An interim constitution was put in place a year earlier at the end of a civil war fought by Maoist rebels.

Source: Al Jazeera and agencies