BEIRUT, A nationwide ceasefire brokered by Russia and Turkey appeared to be holding in most Syrian areas on Friday, despite sniper fire on one area on the outskirts of the capital Damascus which killed one person, a monitoring group reported.

"One person was killed in the sniper fire in the eastern Ghotta region. This is the first civilian casualty since the ceasefire went into effect 17 hours ago," the head of the Britain-based Syrian Observatory for Human Rights, Rami Abdel Rahman, said.

He added that a new wave of shelling has also targeted areas in the northern countryside of Daraa, injuring several people.

But despite the breaches, Abdel Rahman insists that the truce seemed to be holding in most areas across Syria.

Earlier clashes erupted between regime forces and opposition fighters in the Wadi Barada region near the capital Damascus, the observatory said.

Fighters from the Fatah al-Sham Front, a formerly al-Qaeda-linked group, also participated in the clashes, according to the watchdog.

The Fatah al-Sham Front and the Daesh extremist militia are excluded from the ceasefire that went into effect at midnight Thursday (2200 GMT).

Following Friday's clashes, government jets bombarded Wadi Barada, located north-west of the capital, the observatory said.

No casualties were reported.

"The Syrian regime has said that Wadi Barada is not a part of the ceasefire. They believe that the Fatah al-Sham Front has cut off the

water supplies to Damascus and have said they will not tolerate this," Abdel-Rahman told dpa, an accusation denied by the opposition.

Springs in Wadi Barada and the nearby Ain al-Fijah are the main sources of water for residents in and around Damascus.

The United Nations has said it is "alarmed" that 4 million inhabitants in Damascus and surrounding areas have been cut off from the main water supply since December 22.

Abu Mohammed al-Bardawi, an activist in Wadi Barada, said the regime carried out more than 20 airstrikes in the area on Friday.

Pro-regime fighters from the allied Lebanese Hezbollah movement are trying to storm Wadi Barada near the Lebanese border, al-Bardawi said via a WhatsApp message.

Houssam al-Shaafi, a spokesman for the Fatah al-Sham Front, wrote on his telegram account that the group "did not attend, or negotiate, or

sign the ceasefire agreement."

"This ceasefire did not tackle the Iranian militia presence and the Russian occupation ... the only solution is to topple the criminal Syrian regime by military operations and holy struggle and any political solution which keeps the pillars of the current regime is considered a betrayal to the blessed revolution which started six years ago," al-Shaafi wrote.

Elsewhere in Syria, regime forces on Friday fired shells at opposition-held areas in the southern part of the province of Aleppo, the observatory said.

Taking advantage of the calm resulting from the truce, anti-government protesters took to the streets on Friday in some opposition-controlled areas of Syria, activists reported.

Demonstrators in the north-western province of Idlib called on the rebel groups to unite and end the regime of Syrian President Bashar


A similar rally was held in the town of Talbisa in the countryside of Homs province in central Syria, the observatory said.

Russian President Vladimir Putin, a main ally of al-Assad, announced the ceasefire deal on Thursday.

Putin said that Russia, Turkey and Iran would act as guarantors.

Russia and Turkey have supported opposing sides in the Syrian civil war, but in recent months they have ramped up efforts to seek a resolution to the conflict, amid a rapprochement in their bilateral


Moscow and Ankara are planning to host talks in January in Astana, capital of Kazakhstan, between the representatives of the Syrian opposition and the government.

The UN Security Council plans to vote Saturday on a Russia-sponsored resolution on the ceasefire as well as on peace talks, Russian UN

ambassador Vitaly Churkin said Friday.

Iranian President Hassan Rowhani is to attend the Astana talks, the Mehr news agency reported on Friday, citing government sources.

Iran is a key regional ally of al-Assad's regime.

The latest ceasefire in Syria comes a week after government forces regained full control of Aleppo thanks partly to Russian military


Syria's crisis started in March 2011 with a crackdown on mostly peaceful anti-government protests.

The conflict soon developed into a full-blown war.