Syrian rushes troops to Aleppo to fight rebels

Zafer Caglayan added that the deteriorating security was behind the closure of a border through which Turkey once exported food and construction materials to the entire Middle East, though the volume of traffic had dropped 87 percent since the Syrian conflict began in March 2011.

“We have serious concerns over the safety of Turkish trucks regarding their entry and return from Syria,” he said, adding that three border crossings were in rebel hands. Syrians seeking refuge or to resupply would still be allowed in.

A Syrian ally before the anti-Assad uprising began 16 months ago, Ankara has since turned into a harsh critic the regime in Damascus has pursued its bloody crackdown on the revolt. Now, Turkish territory along the of the countries’ 911-kilometer (566-mile) border is used as a staging ground for rebel fighters as well as a haven for thousands of refugees fleeing violence that activists say has killed 19,000 people so far.

Even Moscow, Syria’s closest international ally, seemed to be running out of patience with the Assad regime when it warned Damascus late Tuesday against any use of chemical weapons. The Kremlin statement reminding Syria of its international obligations followed the Assad regime’s announcement earlier this week that it has chemical weapons and would use them in case of foreign aggression.

Russia’s warning reflected a degree of irritation with Assad and followed earlier Russian rebukes over the heavy-handed use of force and slow pace of reforms.

In remarks Wednesday, however, Russian Foreign Minister Sergei Lavrov was back in his old role of Syria’s defender, criticizing new European efforts to enforce an arms embargo as “unilateral sanctions” and a “blockade.”

In Damascus, the new commander for the 300-member UN observer force, Lt. Gen. Babacar Gaye, and the U.N. official for peacekeeping operations, Herve Ladsous, were assessing the prospects for a U.N. peace plan that has been widely ignored by both sides.

Half of the 300-member U.N. observer force, meant to monitor the non-existent ceasefire, has left the country.

“I think diplomats have to be optimistic and that’s no joke, I think we have to hope,” Ladsous told reporters. “We have to hope that the whole process gains traction, that the vicious circle of violence can cease, and that some political solution and first and foremost some political dialogue can get started.”

• Associated Press writers Suzan Fraser from Ankara, Bassem Mroue in Beirut, Natalya Vasilyeva in Moscow and Adam Schreck in Dubai contributed to this report.

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