An international conference aimed at ending the civil war in Libya has called on all parties to accept an "immediate comprehensive ceasefire".
US Secretary of State John Kerry said he expected Libya's rival governments to sign a UN-backed agreement on Wednesday to form a unity government.
The conflict had "gone on too long", he said, and the power vacuum had been "readily filled by extremists".
Libya has been unstable since Muammar Gaddafi was toppled in October 2011.
There is growing concern that the Islamic State group (IS), with a stronghold in the city of Sirte, is profiting from the instability.
Delegates from the two opposing administrations were at the talks in Rome, along with members from Western and Middle Eastern countries and the UN.
Mr Kerry said "no-one understands the need" for a ceasefire better than the Libyan leaders, and said the whole process had been driven by them. "Libyans have negotiated with Libyans," he said.
The rival governments agreed at talks in Tunis two days ago to sign the UN-backed political agreement on Wednesday, and Mr Kerry said he expected that to go ahead.
And when the unity government is formed, he said, the international community is "prepared to meet with it rapidly in order to begin to lay out the possibilities for what is needed in order to facilitate their capacity to govern". ( BBC )
