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A U.S. official hailed Russia's top Middle East envoy for saying rebels could defeat Syria's Assad regime, Moscow's first public admission of the prospect.
"We want to commend the Russian government for finally waking up to the reality and acknowledging that the regime's days are numbered," State Department spokeswoman Victoria Nuland said in Washington.
"I think the question now is: Will the Russian government join those of us in the international community who are working with the opposition to try to have a smooth democratic transition," Nuland said.
Her comments followed remarks by Mikhail Bogdanov, Russia's top envoy for Middle East affairs, to a Kremlin advisory group and oversight committee.
"We have to look squarely at the facts -- the trend is that the Syrian regime and government are losing more and more control and more and more territory," he said in remarks reported by the Russian non-governmental Interfax news agency and state-owned news agency RIA Novosti.
"Unfortunately, it is impossible to rule out a victory of the Syrian opposition," he said.
Kremlin presidential spokesman Dmitry Peskov denied Bogdanov's comments pointed to a change in Russia's position toward Syria.
Peskov said Bogdanov, a deputy foreign minister, was simply speaking about Syria's deteriorating situation, which he called "very bad."
But he said, "We're not fans of the Assad regime and we understand that it can hardly survive, but we also understand that's a decision for the Syrian people to make."
Russia has long backed President Bashar Assad and frequently admonished the West for what it described as interference in Syria's internal affairs. Moscow helped shield Assad's regime from U.N. Security Council censure and sanctions.
The Kremlin's assessment was reinforced when NATO Secretary-General Anders Fogh Rasmussen told reporters in Brussels: "I think the regime in Damascus is approaching collapse. I think now it is only a question of time."
Rasmussen said the reported use of Scud tactical ballistic missiles by the Assad regime showed "utter disregard" for Syrian lives.
Syria's Foreign Ministry denied Thursday using Scud missiles against rebels.
A bombing in the Damascus suburb of Qatana Thursday killed at least 16 people, the state-run Syrian Arab News Agency reported. The Assad regime blamed the bombing on rebels, the agency said, identifying them as "terrorists."
The opposition Local Coordination Committees of Syria said the regime shelled two other Damascus suburbs. One shelling in Jdeidet Artouz al-Fadal killed at least 17 people and a shelling of a bakery in Hajar al-Aswad killed at least four.
The group said the Free Syrian Army, the opposition's main fighting force, destroyed two regime tanks on the road to Damascus International Airport. It also reported fresh soldier defections. SANA reported none of this.
All told, 138 people were killed Thursday, the group said.