Kerry said the “bedrock” of the new deal was an agreement that the Syrian government would not fly combat missions in an agreed area on the pretext of hunting fighters from the banned Nusra Front, an Al-Qaeda affiliate in Syria.
Fighting continued in the hours after the deal was clinched, with at least 58 civilians were killed in the marketplace bombing in rebel-held Idlib, according to rescue workers and Britain-based Syrian Observatory for Human Rights.
Numerous dead were women and children who ventured out into the market to buy supplies for Eid al-Adha, the Muslim holiday that begins on Monday just as the ceasefire is due to come into force.
The Observatory and the LCC reported airstrikes in other parts of the country including the northern province of Aleppo that has been the center of violence in recent weeks.
The Iranian spokesman, however, underlined that the ceasefire does not apply to the terrorist groups, including Daesh (ISIL), al-Nusra Front or other newly-born offshoots, calling on the global community to keep battling against the Takfiri extremists seriously, without any consideration and incessantly.
The two powers back opposing sides in the conflict, with Moscow supporting the regime of President Bashar al-Assad and Washington backing a coalition of rebels it regards as moderate.
The agreement envisages joint US-Russian military strikes against militant groups in Syria, including Daesh.
Syria’s five-year conflict has killed thousands in Aleppo, the main focus of clashes between insurgents, including foreign-backed rebels, and pro-government forces backed by Russian Federation and Iran.
Leading HNC member Bassma Kodmani told AFP that her group “cautiously welcomed” the deal but was sceptical that Damascus would comply. The Syrian Civil Defense, also known as the White Helmets, said helicopters dropped crude barrel bombs on the area.
Both sides agreed not to release the documents publicly.
US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov said that the truce, reached late on Friday, would come into force on Monday, the first day of the Muslim holiday of Eid al-Adha.
Residents of rebel-controlled eastern Aleppo expressed dismay that the cease-fire deal was reached only after government loyalists had succeeded in imposing a total siege of opposition areas by seizing control of the last rebel-controlled route on Sunday.
Hours after the deal was announced, Syria’s army attacked rebel-held areas in Aleppo, as it tries to maximize gains before the ceasefire begins.
According to its terms, both Assad’s forces and rebels would halt attacks, while the US and Russian Federation would join forces against the Islamic State of Iraq and Syria (ISIS) and al Qaeda-linked militants in Syria.
The leader of at least one USA -backed rebel faction has publicly called the offer a “trap”.
The key element is that Russian Federation is then supposed to restrain the forces of President Bashar Assad of Syria from conducting any air operations over areas held by Nusra and other opposition forces.
Meanwhile, Israeli aircraft struck Syrian army positions on Saturday after fire from its war-torn neighbour hit the Israeli-held zone of the Golan Heights earlier in the day, the military said.
Foremost is the question of whether there are meaningful enforcement mechanisms to deter the government from continuing to bombard civilians and regain territory from rebel groups.