A Turkish official also said his nation has held discussions with NATO allies, including the United States, on using Patriot missiles to protect a safe zone inside Syria.
The developments came within hours of President Obama’s re-election. U.S. allies anticipate a new, bolder approach from the American leader to end the deadlocked civil war that has killed more than 36,000 people since an uprising against Mr. Assad began in March 2011.
U.S. officials said Patriots or other assets could be deployed to Turkey’s side of the border for defensive purposes against possible incursions, mortar strikes and the like.
But Washington isn’t prepared to send any such equipment inside Syria, which would amount to a violation of sovereignty and a significant military escalation, said the officials, who spoke on condition of anonymity because they weren’t authorized to speak publicly on the matter.
Like Britain, American officials are considering meeting with rebel military commanders. If the contacts were to happen, they would be most likely conducted by Robert Ford, the former U.S. ambassador in Damascus, who is currently in Doha for Syrian opposition talks, a U.S. official said. But no final decision has been made.
British Prime Minister David Cameron, visiting a camp for Syrian refugees in Jordan, said the U.S., Britain and other allies should do more to “shape the opposition” into a coherent force and open channels of communication directly with rebel military commanders.
Previously, Britain and the U.S. have acknowledged contacts only with exile groups and political opposition figures — some connected to rebel forces — inside Syria.
“There is an opportunity for Britain, for America, for Saudi Arabia, Jordan and like-minded allies to come together and try to help shape the opposition, outside Syria and inside Syria,” Mr. Cameron said. “And try to help them achieve their goal, which is our goal of a Syria without Assad.”
The Foreign Ministry official, who spoke on condition of anonymity in line with department policy, said discussions about the deployment of Patriot missiles to protect a safe zone had been put on hold until after the U.S. election.
Since the summer, Mr. Assad’s regime has significantly increased its use of air power against rebels as government forces are stretched thin on multiple fronts.
The Turkish official said any missile deployment might happen under a “NATO umbrella,” though NATO has insisted it will not intervene without a clear U.N. mandate.
“With the re-election of Obama, what you have is a strong confidence on the British side that the U.S. administration will be engaged more on Syria from the get-go,” said Shashank Joshi, an analyst at London’s Royal United Services Institute, a military and security think tank.
On the ground in Syria, rebels made a new push into the capital Wednesday. Opposition fighters fired mortar shells toward the presidential palace — but missed their target — and clashed heavily with troops in the suburbs of Damascus. The regime’s capital stronghold has seen a surge in violence this week with some of the fiercest clashes in months.
The Britain-based Syrian Observatory for Human Rights and the Local Coordination Committees said the Syrian military was shelling another suburb, Beit Saham, with tanks and mortar shells, killing at least 18 people in that neighborhood alone.