Updated

Delegations representing the Syrian regime and its main Western-backed opposition have reportedly agreed to start direct talks when negotiations resume on Friday.

Russian Foreign Minister Sergey Lavrov told Sky News that he had held discussions with Syrian Foreign Minister Walid al-Moallem and the Syrian National Coalition's Ahmed Jarba after a contentious first day of talks Wednesday that featured accusations of wrongdoing from both sides of the conflict.

Lavrov told Sky News that he had urged both sides not to focus on replacing Syrian President Bashar Assad, adding, "The main thing is to start the process."

United Nations mediator Lakhdar Brahimi told a news conference that he had held separate talks with both sides and noted that he had "some fairly clear indications that the parties are willing to discuss issues of access to needy people, the liberation of prisoners and local cease-fires."

The government's determination to keep Assad in power appears to have strengthened after Secretary of State Kerry stated that Assad had lost his legitimacy by crushing the protest movement against his regime that started in early 2011.

"We really need to deal with reality," Kerry said. "There is no way possible in the imagination that the man who has led the brutal response to his own people could regain the legitimacy to govern."

The Syrian Foreign Minister refused to offer comment on Kerry's statement, telling the secretary of state that only the Syrian people could decide Assad's future. The Syrian National Coalition and its Western allies have advocated the creation of a transitional national government and the rebels have said that any push from the government to secure Assad's power would result in them ending the talks.

At the World Economic Forum in Davos, Iranian President Hassan Rouhani called Thursday for a new election in Syria, saying his nation would respect the results.

"The best solution is to organize a free and fair election in Syria" and, once the ballots are cast, "we should all accept" the outcome, he said.

Iran, a close ally of Assad's, was barred from participating in the Swiss-based talks to end Syria's civil war

At least 130,000 people have been killing in the fighting that began with a peaceful uprising against Assad's rule, according to activists, who are the only ones still keeping count. The fighting in Syria has become a proxy war between regional powers Iran and Saudi Arabia, and taken on post-Cold War overtones with Russia and the United States backing opposite sides.

Syria's ambassador to the U.N., Bashar Jaafari, said Wednesday that his government had offered a cease-fire in the northern city of Aleppo and had yet to hear back from the Americans. U.S. officials have described that as "a capitulation initiative" in the war's most contested city, and not a truce. And rebels within Syria say the government has used past cease-fires to buy time or consolidate gains.

The leader of Al Qaeda called on rival Islamic groups in Syria to end their infighting and focus on battling Assad's forces in a recording released Thursday, Fox News confirmed.

The call by Ayman Al-Zawahiri came as activists said that fighting between the Al Qaeda-linked Islamic State of Iraq and the Levant and an array of other Islamic militant groups intensified in northern Syria.

The Britain-based Syrian Observatory for Human Rights said "Islamic State" fighters fully captured the northern town of Manbij on Thursday after days of fighting.

The Observatory said that 1,395 people, mostly rebel fighters, have been killed since the infighting began Jan. 3, the worst clash among opposition groups since Syria's crisis began in March 2011.

Zawahri said the internal fighting "between the holy warriors of Islam has bloodied our hearts" and that it should stop immediately. He called on Islamic groups in Syria to set up an Islamic court that would mediate and resolve their differences.

He said Islamic fighters should focus on "bringing down Assad's secular, sectarian, unjust and criminal regime to set up a just Islamic state."

Zawahri's 5-minute audio message was posted online Thursday to websites commonly used by militant groups.

Fox News' Catherine Herridge and The Associated Press contributed to this report. 

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