Damascus aims to "recover every area from the terrorists, and to rebuild," Assad said on Monday.

"The armed forces are continuing their work, relentlessly and without hesitation, regardless of internal or external circumstances," the president said in Daraya, where he marked the first day of the Muslim Eid al Adha holiday.

The Syrian regime reclaimed Daraya last month, allowing the rebels and residents to evacuate. Officials have since praised it as a model for other cities and rebels strongholds throughout the country.

On Monday, Assad criticized his opponents for persisting in the fight, which was sparked by anti-government protests in 2011.

"After five years, some people still haven't woken up from their fantasies," he said. "Some were betting on promises from foreign powers, which will result in nothing."

Opposition wants 'guarantees'

Assad's remarks on reclaiming Syria come after US and Russia agreed to a long-awaited truce, which started at sundown on Monday. The country's opposition forces, however, had yet to sign on to it, skeptical of Assad's commitment to the deal.

"We want to know what the guarantees are," Salem al-Muslet, a spokesman for the High Negotiations Committee, the main opposition umbrella group, told the AFP news agency.

"We are asking for guarantees especially from the United States, which is a party to the agreement."

The opposition groups are expected to back the truce in a statement later on Monday, while also highlighting their "harsh reservations and observations" on the deal.

"But as a final takeaway, we do agree," an unnamed source told Reuters.

Uptick in fighting as deadline looms

UN envoy for Syria, Staffan de Mistura, said his office would monitor the start of the ceasefire "carefully, before making any hurried comments." His staff would issue no statements on the truce before Tuesday afternoon, he told AP.

The Kurdish YPG militia already confirmed it would halt offensive operations in Syria, in accordance with the US-Russian agreement.

Syrian government forces and Russia were continuing to bomb opposition areas in Aleppo and other rebel-held areas, according to activists from the scene. Al Qaeda also pushed on with an offensive in the south of the country.

dj/rc (AP, AFP, dpa)