TRIPOLI, Libya (AP) -- Two Libyan militias called Tuesday for legislators to step down or be detained, an ultimatum that escalates a political standoff in the North African nation. The head of Parliament refused and called it an attempted coup.
Parliament's term expired on Feb. 7, but lawmakers voted to extend it with plans to hold new elections in the spring. Since then, hundreds of protesters have held daily demonstrations demanding the legislative body be dissolved.
Rival militias, which wield the real power in Libya, have lined up behind competing political factions in what has become a power struggle between Western-backed Prime Minister Ali Zidan and Islamist factions in parliament that are trying to remove him. Tuesday's ultimatum raised fears the situation could devolve into armed confrontation.
It came a day after Libyans marked the third anniversary of the start of their revolution that toppled longtime dictator Moammar Gadhafi but left the country with no strong central government or military. Successive governments have relied on former rebels who fought Gadhafi to fill the security vacuum, but the fighters formed armed groups that have gradually turned the country into fiefdoms independent from government authority.
The al-Qaaqaa and al-Sawaaq militias called on the parliament "to hand over power" by 9 p.m. (1900 GMT), saying lawmakers who refuse to do so will be considered "usurpers" and will be detained. Several militiamen appeared on TV, with one reading out the joint statement.
The commander denounced Islamists saying they are an "epidemic disease for which we will be the cure" and vowed, "in front of God and the people that we are not and we will not be seekers of power ... but protectors of the nation until it stands on its feet to build its military and security institutions."
The Libya International Network later broadcast live exercises of men in uniform with a timer counting down the five-hour period given in the ultimatum. Movement of those forces was likely to provoke rival militias in the city of Misrata into action as they back the Islamist factions in parliament.
However, the five-hour ultimatum expired without major forces' deployment to the convention center where the parliament convenes. Tripoli-based militias were on alert with militiamen gathered inside their camps waiting for commanders' orders.
Nouri Abu Sahmein, the head of parliament, denounced the warning in a statement televised from inside the building housing the legislative body.
"The General National Congress ... rejects all these attempts and considers them a coup against the legitimate institutions and the choices of the Libyan people," he said, adding that he has received promises of protection from the military and other militias. "We will not permit internal fighting among the Libyans."
The National Forces Alliance -- which is among the largest blocs in parliament and backs Zidan -- distanced itself from the militias in a statement on its official Facebook page, insisting it has "no armed wings" and saying efforts to defuse the situation "requires contacting the group that delivered the statement."
The United Nations urged rival factions to avert violence and to hold a meeting to reach an agreement to spare Libya "a grave crisis that threatens its security and stability."
"The UN Support Mission in Libya (UNSMIL) calls upon political parties, the revolutionaries, the activists and personalities to uphold the high national interest and refrain from resorting to force to resolve political disputes and avert the risks which could lead the country to slide into lawlessness and chaos," it said in a statement.
According to Libya al-Ahrar TV network, UN envoy to Libya Tarek Mitri will meet late Tuesday with commanders of the militias that issued the warning. Zidan, the prime minister, held an emergency meeting as well with the rival factions, according to a statement posted on the government official Facebook page.
The 200-member parliament was chosen in June 2012 to help pave the way for a new constitution to be written and new elections held, with a deadline of Feb. 7, 2014. But the political process stalled amid fierce bickering and violence. The election of the panel tasked to draft the constitution is scheduled to take place on Feb. 20.
Lawmakers led by Islamist factions initially voted to extend their terms without holding new elections but then relented to public outrage and agreed Sunday to hold a new vote, although they did not set a date and failed to appease their opponents.
The weak central government has failed to rein in the multiple militias in the country. Zidan was briefly kidnapped by militiamen in October. Over the summer, eastern militias seized control of oil exporting terminals, sending production plunging from 1.4 million barrels a day to around 600,000, robbing the country of its main revenue source. Other militias in the south have cut off water supplies to the capital for days.