The U.N.'s Libya envoy told rival sides attending new peace talks on Wednesday that the North African "country really is at the limit" and risks becoming a failed state.

U.N. Support Mission in Libya chief Bernardino Leon exhorted those attending talks in Algiers to acknowledge their common interests, particularly their fight against the Islamic State group, and to stop demanding new concessions of each other.

Libya's ambassador to the United Nations said Tuesday that his government is refusing to give its consent for U.N. action aimed at endorsing Europe's military plan to fight migrant smugglers in the Mediterranean.

Ambassador Ibrahim Dabbashi told AFP that as long as European governments were discussing the plan with Libyan militias that control coastal territory, there would be no green light for a U.N. resolution.

The U.N. envoy for Libya said Tuesday, ahead of renewed peace talks, that there can be "no military solution" to the conflict in the country where rivals cannot "win a war."

"There's no military solution" in Libya, U.N. Support Mission in Libya chief Bernardino Leon told the U.S.-Islamic World Forum in Qatar, saying a meeting of Libyan parties and political leaders will begin in Algeria Wednesday.

Libya's internationally recognized government called for outside help against military advances in the country by the Islamic State jihadist group and warned of an Iraq-like scenario.

"Libyan cities are coming under increased threat from this group and it will become difficult to confront them, like in Iraq," Prime Minister Abdallah Thani told a press conference on Sunday in Al-Baida in eastern Libya where his administration is based.

Libya's Tripoli-based government on Sunday called for an armed "mobilization" against the Islamic State group after the jihadists claimed a suicide bombing that killed five fighters allied to the government.

A statement by the Tripoli government, which is not recognized by the international community, urged "officers, soldiers... and all security forces and revolutionaries to mobilize" against IS.

The Islamic State group on Sunday declared "war" on the powerful Fajr Libya militia alliance that controls Tripoli and claimed a suicide bombing that killed five of its fighters.

The dawn blast in northwest Libya is the latest in a series of attacks by IS in the politically divided North African country, where the jihadists have exploited chaos to gain a growing foothold.

"We need your help, we need your help, please," pleads a desperate voice down the phone to the Italian coastguards.

The chaotic call, made by satellite phone in broken English from a boat somewhere in the Mediterranean, is just one of many regularly received by staff at the service's emergency operational center in southern Rome.

Dozens of Tunisians held in Libya by a militia forming part of an alliance ruling Tripoli have been freed, Tunisia's foreign ministry announced Saturday.

"All the Tunisians being held in Libya have been freed. The final group was released today," the ministry said in a statement, without giving numbers.

The Islamic State jihadist group has seized control of the airport in the city of Sirte after forces of a Tripoli-based Libyan government withdrew, a spokesman said Friday.

Mohamed al-Shami, whose government is not recognized by the international community, said its forces pulled out late Thursday from the airport which had "fallen into the hands of the IS organization."

A total of 741 migrants who set sail from Libya in the hopes of reaching Europe were rescued in the Mediterranean on Thursday, the Italian coastguard said.

The rescue operation was coordinated by the coastguard, a spokesman told Agence France Presse, and carried out with the help of German, Irish and British naval vessels under the auspices of the EU's Frontex border control agency.