Separate bomb attacks claimed by the Islamic State group in Syria today killed at least 119 people as Washington pursued efforts for a ceasefire.
As US Secretary of State John Kerry said a provisional deal had been reached on the terms of a truce, violence intensified on the ground.
Double car bombings killed at least 57 people and wounded dozens in the Al-Zahraa district of the central city of Homs, the Britain-based Syrian Observatory for Human Rights monitor said.
And near Damascus, a series of bomb attacks, including a car bombing, ripped through the area of the Sayyida Zeinab Shiite shrine and killed 62 people, the monitor said.
The jihadist IS said it was behind the carnage.
State television footage from Homs showed emergency workers carrying a charred body on a stretcher past devastated shops and mangled cars and minibuses.
The attack was the worst since twin blasts in October 2014 hit a school, killing at least 55 people, including 49 children. Al-Zahraa - whose residents are mostly from the same Alawite sect as Syria's ruling clan - has been regularly hit.
IS, which last month claimed a double bombing that killed 22 people, said it carried out the latest attack.
Two jihadists drove explosive-laden cars into crowds of residents, it said in an online statement.
The group also said two of its suicide bombers carried out the Sayyida Zeinab bombings.
State television said a car bombing and two suicide attacks hit the area, killing 30 and wounding dozens, whereas the Observatory gave a death toll of 62 in four attacks.
IS was also behind a massive attack in January that killed 70 people near the shrine, which contains the grave of a granddaughter of Prophet Mohammed and is revered by Shiites.
World powers have been pushing for a halt in fighting in Syria that was meant to take effect by Friday, but have struggled to agree on the terms.
The latest bombings came as Kerry said he had spoken with his Russian counterpart Sergei Lavrov and agreed on how to implement a ceasefire.
"We have reached a provisional agreement, in principle, on the terms of the cessation of hostilities that could begin in the coming days," Kerry said in Amman.
"It is not yet done and I anticipate that our presidents, President (Barack) Obama and President (Vladimir) Putin, may well speak somewhere in the next days or so in order to try to complete this task."
World powers proposed the truce just over a week ago as part of a plan that also included expanded humanitarian access, in a bid to pave the way for peace talks to resume.
The talks, which collapsed earlier this month in Geneva, had been scheduled to resume on February 25, but the UN's Syria envoy has already acknowledged that date is no longer realistic.
Assad, meanwhile, told Spain's El Pais newspaper he was "ready" for a ceasefire, but said it should not be exploited by "terrorists".
