IS seized control of Sirte, which is 450 km east of Tripoli, in June and fighting flared up again last week with up to 200 dead, according to Libya's ambassador to France, Chibani Abuhamoud.
Battles in former dictator Moamer Kadhafi’s hometown are reportedly fierce. Last week, jihadists beheaded 12 local militiamen, according to the official news agency Lana.
Both of Libya's rival governments - one based in Tobruk, the other in Tripoli - have encouraged militias to take up arms against the jihadists but to little avail.
Although air strikes alone would not suffice to rout IS, also known as Isis, in Sirte, Western diplomats are not ruling them out.
In an interview with RFI, the British ambassador to Libya, Peter Millett, said they would be part of a future “global plan”.
“We need a global plan which involves first and foremost the Libyans themselves but also the countries of the region and other countries threatened by the organisation and that means European countries as well,” he explained in a phone interview from Tunisia. “So we need to put together an overall plan for dealing with it, which no doubt could involve air strikes.”
Nato nations, often criticised for the military intervention that led to Kadhahi’s 2011 downfall, may this time prefer to “lead from behind”, leaving air strikes to regional powerhouses like Egypt, boosted by recent deliveries of F-16 warplanes by Washington and Rafale fighter jets from France, and the United Arab Emirates (UAE).
“I think they have decided that there won’t be any Western military activity in Libya -- certainly not until there is a government of national unity and that does not look any closer,” said Charles Gurdon, political risk consultant with London-based Menas Associates.
But analysts disagree on whether Egypt and the UAE can afford to be involved.
“The Emirates is really preoccupied with the war in Yemen right now and it’s unclear to me if Egypt has the capacity itself to carry out these strikes so it’s a question of military capability right now,” said Frédéric Wehrey, a Carnegie Endowment for International Peace fellow. “The other question is: are air strikes enough to dislodge the Islamic State from Sirte? History shows us from the ongoing American campaign in Syria and in Iraq that it’s not.”
A military solution would do little to resolve the underlying political problems, according to many observers and diplomats.
“Bombing Sirte, bombing Isis is not going to make a huge difference – even if the United States does it,” said Hafed al-Ghwell, an Atlantic Council fellow. “The problems in Libya are bigger than just Isis to be honest.”
In Europe there are nonetheless heightened concerns that Libya may turn into a failed state on its doorstep.
"Timing is crucial and is not unlimited, especially now that the presence of [the Islamic State] in Sirte has taken worrying proportions," Italy's foreign minister Paolo Gentiloni told the La Stampa newspaper in an interview on Monday.
Fears of a failed state next door were echoed by Ambassador Millett.
“There’s certainly a possibility of that happening with the range of terrorist organisations, of different militias, of different political bodies as well,” he said. “Obviously, Libya is different but I think the risk of a failed state is the reason we’ve all been putting our efforts into reaching a political solution – and that political solution will no doubt have to be backed up with significant offers of assistance to re-establish stability, to reestablish security.”
Western nations have often warned against a military solution, urging warring factions in Libya to join the ongoing UN-brokered peace talks in Geneva.
At the weekend, the US, France, Germany, Italy, Spain and Britain again condemned the Islamic State for its “indiscriminate acts of violence” in Libyan.
In a statement, the Western countries called on parties in Libya "to join efforts to combat the threat posed by transnational terrorist groups exploiting Libya for their own agenda”, adding that the situation in Sirte underscored the "urgent need for parties in Libya to reach agreement on forming a government of national accord”.
UN mediator Bernardino Leon has said that there could be an agreement by September, but progress at the Geneva talks has been slow.
A partial deal was reached in July, but leaders of the Tripoli-based General National Congress boycotted the pact, calling it "unsatisfactory".
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