Jaish al Islam, a militant group which controls the town of Douma, denies Russian claims that it agreed to evacuate the last pocket of eastern Ghouta.
A Syrian opposition group said on Friday that UN-mediated talks with Russia were "heading in the right direction" but denied it had agreed to evacuate the last opposition-held enclave in eastern Ghouta.
The town of Douma, controlled by the Jaish al Islam militant group, is the last patch of eastern Ghouta still held by militants who have been routed in a ferocious offensive by the Russian-backed Syrian regime forces that began in February.
The Russian news agency Interfax quoted the Russian military's general staff as saying it had reached agreement with militants in Douma to leave, without saying where they would go.
"Agreement was reached today with the leaders of illegal armed groups on the departure in the near future of the militants and their family members from the town of Douma," it cited Sergei Rudskoy, an official with the general staff, as saying.
The Jaish al Islam military spokesman quickly denied the report.
"Our position is still clear and firm and it is rejecting forced displacement and demographic change in what remains of eastern Ghouta," Jaish al Islam military spokesman Hamza Birqdar said in a message posted on his Telegram feed.
But Mohammad Alloush, the group's political official, said the talks over Douma were moving in the right direction and the "chances [of agreement] are getting stronger day after day".
Thousands leave for northwestern Syria
Rudskoy said over 143,000 people, including 13,793 militants and 23,544 members of their families have left eastern Ghouta.
He also said 40,000 people had returned to their homes there, after the operation to retake the enclave from militants.
The recovery would seal a major victory for the Syrian regime leader Bashar al Assad, crushing the last big opposition stronghold near Damascus seven years into a conflict that has killed over 400,000 people and displaced millions.
Thousands of people – militants from other opposition factions, their families and other civilians – have been leaving for northwestern Syria from other parts of eastern Ghouta in convoys of buses that have been given safe passage to Idlib province.
Jaish al Islam has so far refused such an evacuation, saying it amounts to forced demographic change by Assad and his allies.
Alloush, who is based outside Syria, made the comments in a report, the accuracy of which he confirmed to Reuters news agency.
Douma is surrounded by Syrian regime forces. There are tens of thousands of civilians in the town.
Hundreds killed in the besieged enclave
The regime offensive in eastern Ghouta has killed more than 1,600 civilians, the Syrian Observatory for Human Rights (SOHR) says.
The Britain-based war monitor said a total of 144,000 people have now been displaced from eastern Ghouta.
While thousands have gone to opposition-held territory near the Turkish border, the bulk of the displaced have fled the fighting to shelters in regime-held areas near eastern Ghouta.