"The (regime) army and its militias have besieged Daraa completely," says opposition spokesman Abu Shaima, adding thousands of people have been encircled in a new regime push.
The Syrian regime and allied troops on Monday laid siege to the rebel-held enclave in Daraa and were poised to gain complete control of the city where opposition against regime leader Bashar al Assad first erupted in 2011, rebels said.
Abu Shaima, a spokesman for the rebel opposition in the southern Syrian city, said several thousand people were now encircled after the regime forces pushed into a main base west of the city before a formal evacuation of rebels opposed to a Russian-brokered surrender deal.
"The army and its militias have besieged Daraa completely," the rebel spokesman said.
A deal was reached on Friday between Russian officers and rebel representatives that surrendered Daraa city along with other towns in the southern province that borders Jordan in another victory for Assad and his Russian and Iranian allies.
Opposition fighters not ready to make peace with the army must first be allowed to evacuate to opposition-held areas in northern Syria before the hand over of weapons and the return of regime control.
The rebels say the deal also does not allow the regime forces to move into their bastions and allows for setting up local forces from ex-rebels under the oversight of Russian military police.
Fighting in Daraa has displaced thousands of people and threatens to uproot many more from their homes, adding to the around 6.5 million people already internally displaced by Syria's seven-year-old conflict that has killed over 450,000 people.
'We don't trust Russians or regime'
"There is a lot of fear about the unknown fate and we do not trust the Russians or regime," Shaima added.
In other parts of the deal, Free Syrian Army (or FSA) – that once received Western support – continued to hand over border posts along the frontier with Jordan, east of Daraa province, that it had been in control of since the early days of the conflict.
The regime forces and its militias won a strategic victory after they captured Nassib crossing, the vital trade route that rebels held for three years.
Russia's evacuation plans
The Russian military plans to evacuate up to 1,000 people via a humanitarian corridor near city of Daraa, Interfax news agency reported on Monday, citing Russia's Centre for Reconciliation in Syria.
People will be evacuated to Syria's northern Idlib province, the centre said, Interfax reported.
The number of villages and towns that have joined the truce in south-western Syria has increased to 90, Russia's RIA state news agency reported on Monday, citing the Centre.