Syrian rebels are gaining ground and might win, Russia's deputy foreign minister said on Thursday, in the starkest such admission from a major ally of President Bashar al-Assad.
"One must look the facts in the face," Russia's state-run RIA quoted Mikhail Bogdanov as saying. "Unfortunately, the victory of the Syrian opposition cannot be ruled out."
Mr. Bogdanov, who is Kremlin's special envoy for Middle East affairs, said the Syrian government was "losing control of more and more territory" and that Moscow was preparing plans to evacuate Russian citizens if necessary.
Advancing rebels now hold an almost continuous arc of territory from the east to the southeast of Damascus, despite fierce army bombardments designed to drive them back.
A car bomb killed at least 16 men, women and children in Qatana, a town about 25 kilometres southwest of Damascus where many soldiers live, activists and state media said.
The explosion occurred in a residential area for soldiers in Qatana, which is near several army bases, said Rami Abdelrahman, head of the pro-opposition Syrian Observatory for Human Rights.
He put the death toll as 17, including seven children and two women. State news agency SANA said 16 people had died.
State television blamed the blast on "terrorists" - its term for rebels - and showed footage of soldiers walking by a partly collapsed building, with rubble and twisted metal on the road.
The attack follows three bombs at the Interior Ministry on Wednesday evening, in which state news agency SANA said five people were killed, including Abdullah Kayrouz, a member of parliament from the Syrian Social Nationalist Party.
Apart from gaining territory in the outskirts of Damascus in recent weeks, rebels have also made hit-and-run attacks or set off bombs within the capital, often targeting state security buildings or areas seen as loyal to Mr. Assad, such as Jaramana, where twin bombs killed 34 people in November.
Insurgents launched an offensive on Damascus after a July 18 bombing that killed four of Mr. Assad's closest aides, including his feared brother-in-law Assef Shawkat, but were later pushed back.
With his back to the wall, Mr. Assad is reported to be turning ever deadlier weapons on his adversaries.
U.S. NATO officials said on Wednesday that the Syrian military had fired Scud-style ballistic missiles, which are powerful but not very accurate, against rebels in recent days.
Human Rights Watch said some populated areas had been hit by incendiary bombs, containing flammable materials such as napalm, thermite or white phosphorous, which can set fire to buildings or cause severe burns and respiratory damage.
The British-based Syrian Observatory said war planes were bombing rebel-held eastern suburbs of Damascus on Thursday and artillery was hitting Daraya and Moadamiyeh, southwestern areas near the centre where rebels have been fighting for a foothold.
At least 40,000 people have been killed in Syria's uprising, which started in March 2011 with street protests which were met with gunfire by Mr. Assad's security forces, and which spiralled into the most enduring and destructive of the Arab revolts.
The United States, European powers and Arab states bestowed their official blessing on Syria's newly-formed opposition coalition on Wednesday, despite increasing signs of Western unease at the rise of militant Islamists in the rebel ranks.
Western nations at "Friends of Syria" talks in Marrakech, Morocco rallied around a new opposition National Coalition formed last month under moderate Islamist cleric Mouaz Alkhatib.
Russia, which along with China has blocked any UN Security Council measures against Mr. Assad, criticized Washington's decision to grant the coalition formal recognition, saying it appeared to have abandoned any effort to reach a political solution.
Mr. Bogdanov's remarks were the clearest sign yet that Russia is preparing for the possible defeat of Mr. Assad's government.
"We are dealing with issues of preparations for an evacuation. We have mobilization plans and are clarifying where our citizens are located," Mr. Bogdanov said.