World Bulletin / News Desk
A landmark truce is to take effect in Syria on Saturday, the United States and Russia announced, but the "cessation of hostilities" does not include the ISIL and Al-Nusra Front, the main factions.
The leading opposition group in the five-year conflict gave its conditional acceptance to Monday's announcement, however Israel said it was sceptical the deal would hold, and analysts warned any pause in the fighting would be dependent on Russia, Iran and President Bashar al-Assad.
The announcement came a day after the deadliest attack in Syria's brutal civil war, with 134 people -- mostly civilians -- killed in a series of blasts near Damascus.
In a joint statement, Washington and Moscow said the partial truce would begin at midnight Damascus time, suspending a vicious conflict that has left more than 260,000 people dead and seen half the population displaced.
"If implemented and adhered to, this cessation will not only lead to a decline in violence, but also continue to expand the delivery of urgently needed humanitarian supplies to besieged areas and support a political transition to a government that is responsive to the desires of the Syrian people," US Secretary of State John Kerry said.
US President Barack Obama and Russia's President Vladimir Putin discussed the deal by phone, the White House said.
Putin said Moscow would do "whatever is necessary" to ensure Damascus respects the agreement.
"We are counting on the United States to do the same with its allies and the groups that it supports," he said.
The two global powers are pursuing separate air wars in Syria, with Russia pounding rebel targets and a US-led coalition focused on IS jihadists.
UN Secretary General Ban Ki-moon called the deal a "long-awaited signal of hope", and urged all sides to abide by it.
Will ceasefire hold?
There was no immediate reaction from Damascus, but the main grouping of opposition factions said it "agreed to respond positively to international efforts to reach a truce deal".
Bashar al-Zoubi, head of the political office of the Yarmouk Army, part of the rebel Free Syrian Army, said that would provide cover for Syrian President Bashar al-Assad and his Russian allies to keep attacking opposition-held territory where rebel and militant factions are tightly packed.
"Russia and the regime will target the areas of the revolutionaries on the pretext of the Nusra Front's presence, and you know how mixed those areas are, and if this happens, the truce will collapse," he said.
Rebel officials said it was impossible to pinpoint positions held by Nusra.
"For us, al-Nusra is a problematic point, because al-Nusra is not only present in Idlib, but also in Aleppo, in Damascus and in the south. The critical issue here is that civilians or the Free Syrian Army could be targeted under the pretext of targeting al-Nusra," said a senior opposition figure, Khaled Khoja.
He said the cessation would be for an initial two weeks and "could be extended indefinitely if the parties commit to it."
Analysts also had reservations about the deal.
"This depends entirely on the good faith of Russia, Iran, and the Assad regime, none of whom have shown much good faith in the last five years," Frederic C. Hof, a senior fellow at the Atlantic Council who formerly worked on US Syria policy, told the New York Times.
Iran has sent military advisers to Syria and the Tehran-backed Lebanese Shiite movement Hezbollah has deployed at least 6,000 militants to fight alongside Assad's forces.
The 17-nation International Syria Support Group backing Syria's peace process agreed at a meeting in Munich earlier this month to implement a ceasefire by last week, but that truce never materialised.