ISTANBUL, Turkey — Russia on Tuesday confirmed that it would ship advanced antiaircraft missiles to the government of Syrian President Bashar Assad, provoking Israel to threaten military action if the weapons are delivered and drawing condemnation from the United States.
Coming just hours after the European Union agreed to let its ban on sending weapons to Syria's anti-Assad rebels expire at the end of this week, the Russian action seemed to foretell a steady escalation of Syria's bloody civil war, with the United States, Britain, France and Persian Gulf states backing the rebels while Russia, Iran and the Lebanese Hezbollah militia offer arms and manpower to the Syrian government.
"It is very, very difficult to know where this process of escalation will stop," strategic analyst Anthony Cordesman said in Washington, noting that the Shiite-Sunni sectarian tensions fueling the Syrian conflict extend as far east as India.
Russian officials portrayed the decision to deliver the S-300 anti-aircraft missiles as a move to stabilize the situation as they negotiate with the United States over the details of a peace conference tentatively set for next month.
"We believe that moves like this one to a great degree restrain some hotheads from escalating the conflict to the international scale," Russian Deputy Foreign Minister Sergei Ryabkov said in confirming the missile shipment, according to the government-allied website Russia Today.
But Israel saw the potential delivery of the air-defense system as changing the balance of power in the region and giving Syria not only a way to ward off attack, but also an offensive weapon that could down planes well outside Syrian airspace. "The missiles are a threat," Israeli Defense Minister Moshe Yaalon said. "Let's hope it doesn't happen, but if it does, we know what to do."
The State Department criticized the Russian plan. "We condemn all support of arms to the regime. We've seen how the regime uses those arms," spokesman Patrick Ventrell told reporters.
At the same time, he welcomed the EU move to permit weapons shipments to the rebels as "part of the international community's efforts to demonstrate its full support for the Syrian opposition."
In new violence Tuesday, gunmen killed three Lebanese soldiers in a drive-by shooting on a government checkpoint near the Syrian border, Lebanon's military said. The shooting added to fears that the crisis in Syria is spilling into Lebanon.
The Lebanese militant group Hezbollah has intervened in the conflict by sending fighters to Syria to support Assad.