Updated

Secretary of State John Kerry says the transfer of advanced missile defense systems from Russia to Syria would be a "destabilizing" factor for Israel's security.

Kerry says the U.S. has expressed concerns about what the S-300 batteries in Syria would mean for Israel's security. He wouldn't address what the missiles might mean for Syria's civil war.

He spoke to reporters in Rome after the Wall Street Journal reported that Russia was preparing to sell the weapons to President Bashar Assad's regime. The report said Israel had warned the U.S. Kerry praised Moscow for helping try to organize Syrian peace talks.

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