The seized oil fields lie south of Rasafa and its oil wells, which the army took last month in their first major territorial gains, inside the province.
The bomber rammed a car full of explosives into a gathering of Hayat Tahrir al Sham rebels affiliated with al Qaeda’s Nusra Front, at a textile factory.
The United States, Russia and Jordan reached the “de-escalation agreement,” at the G20 summit, ahead of the UN-based peace talks set to open this week.
The Syrian army said it would suspend combat operations in southern Syria until Thursday but rebels said the army had already violated the ceasefire.
There was no immediate claim of responsibility for the attack, which pro-Damascus media said was carried out by a suicide car bomber.
Under the operation Turkey took the border town of Jarablus on the Euphrates river and cleared ISIS fighters from a roughly 100-km stretch of the border.
On the ground, rebels faced continued fighting on two fronts, which could undermine the deal.
Bashar al-Assad, also said his government was ready to negotiate on “everything” at peace talks his Russian allies hope to convene in Kazakhstan.
In a statement, the rebel groups also said that any territorial advances by the army and Iran-backed militias that are fighting alongside it would end the fragile ceasefire brokered by Russia and Turkey.
The rebels have taken Qabasin, several miles northeast of al Bab, setting the stage for an assault on the last urban stronghold of ISIS in northern Aleppo.
Syrian President Bashar al-Assad and his allies believe that Trump’s vctory saved them from the risks of an interventionist Clinton administration.
The Observatory said at least 38 people including 14 children had been killed in rebel shelling of government-held areas of Aleppo in the last 48 hours.
The Syrian Observatory for Human Rights has observed a significant drop in the violence in areas covered by the truce.
The commander, Abu Hajer al Homsi, was killed in a rural area of Aleppo province in a strike targeted at a meeting of the group’s leaders.
Turkey has revealed little about the strategy behind its first major incursion into Syria, beyond saying it wants to drive ISIS and Kurdish fighters away from the border.
The Syrian army said it had repelled the attack and killed hundreds of insurgents.
Instead of finding defenders of besieged Sunni Muslim communities, defectors often found ISIS to be merciless with anyone who opposed its rule.
The truce between the army and rebels is the first since February, but opposition groups and a monitoring organisation say little has changed on the ground.