Egypt called Tuesday for UN-backed international intervention in Libya after launching air strikes on Islamic State targets in retaliation for the jihadist group's beheading of Egyptian Christians.
The matter will be taken up by the UN Security Council on Wednesday after a request by Egyptian Foreign Minister Sameh Shoukry, diplomats said.
President Abdel Fattah al-Sisi said "there is no choice" but to create a global coalition to confront the extremists in Libya.
Shoukry was in New York seeking backing for military intervention and to demand "full support" against the jihadists, his ministry said.
Arab diplomats have expressed support for Egypt's request, but said they thought it would also require formal backing from Libya.
But Libya currently has two rival parliaments and governments, one side with ties to Islamists and the other recognised by the international community.
The diplomatic push comes a day after Egyptian F-16s bombed militant bases in Derna and on the fourth anniversary of the beginning of the 2011 NATO-backed revolt that ousted dictator Moamer Kadhafi.
The raids were ordered hours after IS in Libya released a gruesome video of the beheadings.
The Copts had been seeking work in Libya when they were captured.
UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein called the murders a "vile crime targeting people on the basis of their religion".
Hundreds of thousands of Egyptians remain in Libya, and Cairo is encouraging them to leave, said foreign ministry spokesman Badr Abdelatty.
Libya has been gripped by turmoil since the revolt and Cairo has long said the NATO intervention to help the anti-Kadhafi rebels left Egypt to contend with chaos on its western border.
- Libya mission 'not finished' -
"The mission was not finished," Abdelatty said.
Signup to our newsletter and follow us on Facebook and Twitter!
France, which agreed Monday to sell Egypt advanced Rafale warplanes, has called with Cairo on the UN to adopt measures to confront the jihadists in Libya.
Italy, the former colonial power there and located just across the Mediterranean, ruled out intervention without UN backing and suggested a political solution remained the best option.
"What is happening is very complicated. We are following events closely and with concern but there is no need to jump from total indifference to hysteria and an unreasonable reaction," Prime Minister Matteo Renzi said.
The European Union said it would discuss with the Egyptian and US governments this week joint action on Libya, but that it saw no role in any military intervention for now.
In Rome, six Western powers stressed Tuesday there was a need for a political solution to the crisis.
The "brutal" beheadings demonstrated "once again the urgent need for a political solution to the conflict," said the statement from the United States, Britain, France, Germany, Italy and Spain.
Chaos in Libya has seen the rival governments and powerful militias battling for key cities and the country's oil riches, providing fertile ground for IS.
Several Libyan groups have pledged allegiance to IS, which last year seized large parts of Syria and Iraq, declaring a "caliphate" and committing widespread atrocities.
Delegates from Libya's rival parliaments held UN-mediated indirect talks this month described as positive.
But Egypt says it would be naive to hope for a speedy settlement, insisting the jihadists must be confronted.
"There are terrorist organisations in Libya that are not abiding by their commitments; they are not serious about dialogue," said Abdelatty.
Monday's strikes were the first time Egypt announced military action against jihadists in Libya. Last year it reportedly allowed the United Arab Emirates to use its bases to bomb militants there.
Experts say Sisi wants to be seen as a key ally of the West against Islamist extremism, deflecting international criticism of his crackdown on the Muslim Brotherhood of former president Mohamed Morsi, whom he ousted in 2013.
As well as Libya to the west, Egypt is dealing with an insurgency in its own east, in the Sinai, where jihadists have also joined IS and killed scores of troops.
Abdelatty said it was time for the international effort against IS -- which has been hammered by US-led air strikes in Iraq and Syria -- to focus on its presence elsewhere.
"Just as there is movement against Daesh in Syria and Iraq, we want the world to turn its attention to Libya," he said, using an Arabic acronym for group.