MOSCOW — Russia’s top Middle East diplomat and the leader of NATO offered dark and strikingly similar assessments of the embattled Syrian president’s future Thursday, asserting that he was losing control of the country after a nearly two-year conflict that has taken 40,000 lives and has threatened to destabilize the Middle East.

The bleak appraisals — particularly from Russia, a steadfast, strategic Syrian ally — amounted to a new level of pressure on the Syrian president, Bashar Assad, who has been resorting to increasingly desperate military measures, including the use of Scud ballistic missiles, to contain an armed insurgency that has encroached on the capital, Damascus.

The Russian diplomat, Deputy Foreign Minister Mikhail Bogdanov, acknowledged that Assad’s forces could be defeated by rebels, whom the Syrian leader has repeatedly dismissed as ragtag foreign-backed terrorists with no popular support.

“Unfortunately, it is impossible to exclude a victory of the Syrian opposition,” said Bogdanov — the clearest indication to date that Russia thinks that Assad could lose.

Bogdanov’s remarks, reported by Russia’s Interfax news service, came as the secretary-general of NATO, Anders Fogh Rasmussen, told reporters in Brussels that Assad’s use of ballistic missiles, which Western officials monitoring the Syrian conflict reported Wednesday — and which Syria has denied — reflected his “utter disregard” for Syrian lives. Rasmussen also predicted the demise of Assad’s government.

“I think the regime in Damascus is approaching collapse,” he told reporters after a meeting with the Dutch prime minister at NATO headquarters. “I think now it is only a question of time.”

While NATO member states have made similar predictions before, the assertion by Rasmussen, the leader of the Western military alliance, reinforced a growing consensus that Assad’s options for remaining in power had been all but exhausted — a view now apparently shared by Russia.

The State Department welcomed Bogdanov’s comments that Assad was losing ground but indicated there was still a wide gulf between the United States and Russia about how to deal with the crisis in Syria.

Victoria Nuland, the State Department’s spokesman, said the United States would like to “commend the Russian government for finally waking up to the reality and acknowledging that the regime’s days are numbered.”

But she said Russia should take steps to facilitate Assad’s departure from power by withdrawing “residual support for the Assad regime.”

While Russia has said it would not sign new military contracts with the Syrian government, it has not promised to sever existing military contracts. Nor has Russia cut off all economic support to the Syrian government, Nuland said.

Throughout the crisis, as it has grown from peaceful protests in March 2011 to engulf the country in armed conflict, Russia has acted as Syria’s principal international shield, protecting Assad diplomatically from Western and Arab attempts to oust him and holding out the possibility of his staying in power during a transition.

RUSSIA PLANS EVACUATION

Only in recent days has Russia’s view seemed to shift, while Assad’s foes, grouped in a newly minted and still uncertain coalition, have garnered ever broader international support as the legitimate representatives of the Syrian people.

“We must look squarely at the facts, and the trend now suggests that the regime and the government in Syria are losing more and more control and more and more territory,” Bogdanov said in remarks to Russia’s Public Chamber, a Kremlin advisory group, according to Interfax.

Russia, he said, was preparing to evacuate its citizens — a complex task, since for decades, Russian women have married Syrian men sent to study in Russia and returned to Syria with them to raise families.

It was the first time an official at Bogdanov’s level had announced plans for an evacuation, which sent a message to the Syrian government that Russia no longer held out hope that the government could prevail. He said Russia had a plan to withdraw its personnel from its embassy in the Syrian capital, Damascus, but that was not yet necessary. Russia’s press attache in Damascus confirmed this, telling Interfax that there was “no sharp deterioration” in conditions there.

Bogdanov offered a dark view of how the conflict would unfold from this point, saying that it took two years for the rebels to control 60 percent of Syria’s territory, and another year and a half will pass before they control the rest.

“If up until now 40,000 people have died, then from this point forward it will be crueler, and you will lose dozens or many hundreds of thousands of people,” he said. “If you accept this price to topple the president, what can we do? We of course consider this totally unacceptable.”

As the Russian official spoke, fresh evidence of the intensity of the battle emerged.

During the civil war, Moscow has been the principal arms supplier for the Damascus government, as it has been for decades. Obama administration and NATO officials said Wednesday that Syrian government forces had resorted to firing Scud missiles at rebel fighters as the government struggled to slow the momentum of the insurgency.

The officials said that over the past week, Assad’s forces for the first time had fired at least six Soviet-designed Scuds in the latest bid to push back rebels who have consistently chipped away at the government’s military superiority.

Syria’s Foreign Ministry denied the assertion Thursday, saying in a statement that missiles “were not used in confronting the terrorist groups.”

Syrian state media and anti-government activists reported that at least 16 people had been killed when a car bomb exploded Thursday near a school in the town of Qatana, southwest of the capital.

The bomb wounded more than 20 people, leaving some in critical condition, according to the Syrian Observatory for Human Rights, which is based in Britain and tracks the conflict through a network of activists. Government forces still hold sway in Qatana, a town with a Sunni Muslim majority and Christian minority, Agence France-Presse reported.

Russia is eager to protect its strategic interests in Syria, including a naval facility at the port of Tartus, and has been meeting frequently with opposition delegations, presumably laying the groundwork for a possible transition. In his remarks to the Public Chamber, Bogdanov said he believed that half the Russian citizens living in Syria supported the rebels.

“Moreover, some of the people coming here as part of opposition coalitions have Russian passports,” he said, according to Interfax.

CHEMICAL WEAPONS

Western intelligence agencies observed Syrian units making advanced preparations for the potential use of chemical weapons, including loading trucks with ready-to-use bombs and shells, prompting President Barack Obama last week to warn Syria against using the banned munitions, according to Western and Middle Eastern officials.

Soldiers at one Syrian base were monitored mixing precursors for chemical weapons and taking other steps to ready the lethal munitions for battlefield use, the officials said. It was the first hard evidence that Syria was moving toward possible activation of its vast arsenal of chemical weapons, which includes nerve gas and other poisons.

Surveillance photos confirmed that at least one army unit began loading special military vehicles that transport bombs and artillery shells carrying chemical warheads, according to the officials. The moves followed specific orders to elite troops to begin preparations for the use of the weapons against advancing rebel fighters, the officials said.

Two Western officials briefed on the intelligence findings said the Syrian government forces stopped the preparations late last week and that there was no evidence that activated chemical weapons were loaded onto aircraft or deployed to the battlefront.

The officials spoke on condition of anonymity because of the sensitive nature of the intelligence. The Obama administration and the CIA declined to answer questions about the episode. Defense Secretary Leon Panetta said this week that the threat had eased, though it had not been eliminated.

Intelligence analysts said the orders to prepare the weapons were issued about two weeks ago. They said it was not clear whether the decision came from senior Syrian leaders, possibly including Assad, or from a field commander acting on his own, the officials said.

Since concerns surfaced in the summer that Syria was moving chemical weapons among several sites across the country, officials in Damascus have repeatedly pledged not to use the banned munitions. After the warnings last week from Obama and other foreign leaders, the Syrian Foreign Ministry repeated that it would not use chemical weapons against the rebel forces.

Information for this article was contributed by Ellen Barry, Rick Gladstone,Alan Cowell,Anne Barnard and Michael R. Gordon of The New York Times and by Joby Warrick of The Washington Post.

Front Section, Pages 1 on 12/14/2012