Beirut: Efforts intensified for a partial truce in Syria as fighting raged near Aleppo on Monday and after the country suffered its bloodiest jihadist attack in nearly five years of war.
US President Barack Obama and Russian counterpart Vladimir Putin are expected to speak in the coming days after Washington announced a provisional agreement had been reached on an imminent "cessation of hostilities".
US Secretary of State John Kerry announced the deal yesterday, as a string of suicide bombings in areas near a Shiite shrine outside Damascus and in the city of Homs killed at least 179 people.
The Islamic State group claimed responsiblity for both attacks in regime-held areas, which a monitor said killed 120 people near the shrine of Sayyida Zeinab and at least 59 in the Al-Zahraa district of Homs.
The bombings near the shrine marked the deadliest jihadist attack since Syria's conflict erupted in March 2011, said the Syrian Observatory for Human Rights, a Britain-based monitoring group.
Kerry said the US and Russian leaders were to speak "in the next days or so" on the terms of implementing the agreement, which would apply to fighting between non-jihadist rebel forces and regime troops backed by Moscow and Tehran.
The partial ceasefire would not extend to international efforts to combat IS and other jihadist groups in Syria, complicating its implementation.
Announced by top diplomats in Munich earlier this month, the ceasefire failed to take hold by last Friday as initially planned.
Part of a plan that also included expanded humanitarian access, the proposal aims to pave the way for a resumption of peace talks that collapsed earlier this month in Geneva.
The talks had been scheduled to resume on February 25, but the UN Syria envoy has already acknowledged that date is no longer realistic.
Syria's main opposition umbrella group, the High Negotiations Committee (HNC), was meeting in the Saudi capital Riyadh today for talks on the ceasefire and peace talks efforts.
Spokesman Monzer Makhous told AFP the meeting was expected to continue for two or three days.
The HNC has said any ceasefire must include provisions for Russia, Iran and foreign militia forces backing the regime to stop fighting.
Russia launched air strikes in Syria last September against what it said were "terrorists" but has been accused of bombing non-jihadist rebel forces in support of President Bashar al-Assad, a longtime ally.