EU urges warlord Haftar to end violence in Libya

The situation risked "escalating to the level of a civil war" and "all Europeans are united in trying to prevent that," she added, after meeting with EU foreign ministers in Luxembourg.

Mogherini spoke, echoing previous calls by the US, amid fighting on the outskirts of Tripoli, which killed at least 27 people in recent days and prompted around another 2,800 to flee the area.

"The fast increasing deployment of forces could potentially result in significant population displacement," the United Nation's humanitarian office said on Monday.

Its staff had around 200,000 emergency medical kits on offer it added, in a sign of how far the escalation could go.

Haftar, a 75-year old former general, already controls most of the country and its oil fields.

But forces loyal to the UN-backed Government of National Accord (GNA) in Tripoli, led by 59-year old Fayez al-Serraj, and local militias have mounted resistance in a crisis with geopolitical implications.

Haftar has close ties to Russia and some commentators fear that his actions could play into Moscow's hands by creating a new wave of refugees to Europe ahead of EU elections in May, which could help far-right and pro-Russian parties to gain votes.

"Europe should be scared," Andras Simonyi, an expert on transatlantic relations at the Johns Hopkins University in Washington, told EUobserver.

"The 2015 refugee crisis was a masterstroke of Putin, by creating a crisis in Syria. This way, Putin will control much of the refugee flow from Africa," Simonyi added, referring to Russian president Vladimir Putin and his military aid for the Syrian regime.

The numbers of migrants coming to Europe via the central Mediterranean dropped 80 percent to just 23,485 last year, according to Frontex, the EU border control agency.

There are about 660,000 migrants currently in Libya, the International Organisation for Migration (IOM), an intergovernmental body based in Geneva, said.

"Many of these have well-established networks and continue to live and work there," IOM spokesman Ryan Schroeder told this website.

"We do not know if the current situation will affect the number of sea departures from Libya. The scenario ranges from very few, given the dangerous conditions for everyone involved, to an uptick if smugglers manage to take advantage of the chaos," he added.

Russia aside, France and Italy have also tried to build ties with Haftar, among belief in Italy's military establishment that he offers the best chance to deliver security in its southern neighbour.

Regional powers Egypt, Saudi Arabia, and the United Arab Emirates have got behind Haftar as well, while Turkey and Qatar have backed al-Serraj's GNA.

Mogherini said on Monday that France and Italy did not object to the EU ceasefire call despite "divisions and different perspectives from some member states" in the past.

The ministers did not discuss the migration threat, she added.

But Libya also posed a wider security threat in terms of weapons and oil smuggling to Europe and the proliferation of Islamist radical groups there, she indicated.

The EU will continue trying to train the Libyan coast guard to intercept people trying to cross the Mediterranean Sea, Mogherini said, even though EU naval patrols in the region, under the so-called Operation Sophia, were recently halted due to Italian objections in what she called a "regrettable" decision.

"Libya is of utmost importance. We must cut the violence as soon as possible," Finnish foreign minister Timo Soini said.

"The situation poses a security threat to Europe ... I'm worried about it," he added.

Libya has been divided by rival groups since US and European air strikes helped to topple its late dictator, Muammar Gaddafi, in 2011.

The renewed fighting in the oil-rich country helped send the price of oil to a six-month high on Monday, creating a windfall for other producers, including Russia and Saudi Arabia.