It was the first official announcement of a delay, which had been widely expected amid ongoing disputes over the rules.

With major mobilisations in Tripoli and other western areas by armed groups, the collapse of the electoral process risks aggravating local disputes and triggering a new round of violence.

Disputes over the path forward could also undo the wider U.N.-backed peace process between Libya's main eastern and western camps that have maintained a ceasefire since last year.

Factions, candidates and foreign powers have been talking behind the scenes about whether an election can still take place with a short delay or whether a longer postponement is necessary to reach agreement on the legal basis of the vote.

Meanwhile, the status of the interim government that was installed in March as part of the same peace process is also at risk, with the eastern-based parliament having withdrawn confidence from it in September.

The parliament's electoral committee's statement on Wednesday added that the government's mandate would expire on Friday.

Reporting by Ayman al-Sahely and Ahmed Elumami, writing by Angus McDowall; Editing by Toby Chopra and Andrew Heavens