Support for Libyan unity government 'crumbling': UN envoy

Support for the UN-backed unity government in Libya is "crumbling" amid increased power outages and a weakening currency that is hitting crucial imports, the United Nations' envoy to the embattled north African country told a newspaper.

The Government of National Accord (GNA) has been struggling to impose its authority on a country riven by political and armed rivalries, posing extra challenges as it tries to quash Islamic State militants.

The UN point man for Libya, Martin Kobler, told Switzerland's Neue Zuercher Zeitung in an interview published on Friday there was no alternative to backing the GNA, but he acknowledged it had forfeited some of its initial popularity.

Asked about an earlier comment he made that 95 percent of Libyans backed GNA Prime Minister Fayez Seraj, he said: "That was in April. There was a lot of good will then for the unity government. It has lost some support in the meantime.

"At the time Tripoli had 20 hours of electricity a day, now it is 12 ... In April people had to pay 3.5 dinars for a dollar. Today it is five dinars. That is devastating for an import-oriented economy. Support is crumbling."

Kobler, a German career diplomat, said US air power could not win the fight against Islamic State in Libya, appealing for squabbling factions to support the GNA.

"Strikes by the Americans alone cannot defeat IS. The fight has to be a Libyan one. It will be won with ground troops," he said.

Blow to IS in Sirte

Pro-government forces battled on Thursday to clear IS from its main Libyan stronghold of Sirte, after dealing a major blow to the group by seizing their headquarters.

IS fighters still control several areas of the Mediterranean city, whose capture in June last year sparked fears that the group would use it as a springboard for attacks on Europe.

The fall of Sirte would be a huge setback to IS efforts to expand their self-proclaimed "caliphate" beyond Syria and Iraq where they have also suffered a string of losses.

Forces loyal to Libya's UN-backed unity government made a significant breakthrough on Wednesday in their nearly three-month-old offensive to retake the city, seizing a conference centre where IS had set up a base.

"The battle for Sirte has reached its final phase, after the successful offensive by our heroes," a spokesman for the forces, General Mohamad Ghassri, said on Thursday in remarks carried by the LANA news agency.

The rapid advance comes after the United States launched air strikes on IS positions in the city for the first time on 1 August.

IS took advantage of the chaos that followed the death of longtime Libyan leader Muammar Gaddafi in 2011 to gain a foothold in the country.

The forces loyal to the GNA on Wednesday also seized the University of Sirte campus just south of the Ouagadougou conference centre as well as the Ibn Sina Hospital to the north.

Libyan television stations broadcast images of flag-waving soldiers in recaptured areas including the Ouagadougou centre, flashing victory signs as they posed for photographs.

The pro-GNA forces said 16 of their fighters were killed and dozens wounded on Wednesday in the fighting in Sirte.

The GNA said that at least 20 militants had died in fighting for the university campus.

In total more than 300 pro-government fighters have been killed and 1,800 wounded in the operation for Sirte, according to medical sources in the city of Misrata, where the operation's command centre in based.