Two Libyan militia have called on Libya's parliament to hand over power, as a standoff between rival armed groups developed a day after the country marked three years of revolution.
The Sawaiq and Qaqa militia brigades, powerful in the Zintan and Tripoli areas, said in a statement that the mandate of the General National Congress ran out on February 7, and that it had hours to leave power.
The 200-member GNC, elected in 2012 and tasked to draft a new constitution, extended its term of power earlier this month, sparking protests.
"In our view the GNC stands for a return of dictatorship," a militia spokesman said in a statement as he was surrounded by fellow fighters shouting "God is great".
However, other militia groups have indictated they would side with the GNC, indicating a standoff that could lead to confrontation in the deeply divided country.
The Tripoli Defence Council, a group of militias in Tripoli aligned with the official security services, announced it would back the "legitimate" government, the GNC. The Misrata Brigades, which have more tanks than the Libyan army, were also said to be in support of the GNC.
Nouri Abusahmain, the president of GNC, rejected the statement by Sawaiq and Qaqa as a coup attempt.
"The GNC has given instructions to the chief of staff to take the necessary steps to deal with this group," he said. "The GNC received confirmation from the head of the army and revolutionaries that they would defend its legitimacy."
Al Jazeera's John Hendren, reporting from Tripoli, said that the militia's ultimatum was the prelude to a standoff.
"Sides are beginning to align, with some militias still in support of the government," he said.
"We could have a standoff. We have the potential for a confrontation, but this is just at the talking stage."
Libya is facing turmoil as the government of the prime minister, Ali Zeidan, is struggling to control armed militias who helped overthrow the former ruler, Muammar Gaddafi, in 2011 and have retained their weapons to make financial and political demands.
Many Libyans blame militias and infighting inside the GNC for a lack of progress in the transition towards democracy since the revolution.
The GNC, which is deadlocked between Islamists and nationalists, had on Monday announced new elections as soon as possible, but gave no date.
Oil production, Libya's lifeline, has slowed to a trickle as armed protesters and tribesmen have seized oil ports and fields across the vast desert nation to press political and financial demands.