Israeli officials reacted with skepticism to the plan proposed by Russia on Monday to transfer Syria’s chemical weapons to international supervision.

Army Radio reported that Israeli leaders believe the proposed deal by Russia, Syria’s ally, should be approached with caution because it may be a manipulative tactic meant only to avert a U.S. strike. The deal—which Russia proposed after U.S. Secretary of State John Kerry suggested, in comments later described by the State Department as “rhetorical,” that Syrian President Bashar al-Assad could avoid a military strike by surrendering his chemical weapons—does not punish Syria for using chemical weapons against civilians.

Israeli President Shimon Peres warned that the Syrians, who welcomed the Russian proposal, have “proved they are not credible and that their integrity should not be trusted.” Member of Knesset Avigdor Lieberman (Yisrael Beiteinu) stressed that the details of the Russian proposal are unclear, and that Israel should remain uninvolved in the Syrian civil war.

“Assad must understand that he and his associates will become a legitimate target, if he drags Israel into the conflict,” Lieberman said.

A senior Israeli diplomatic official told Army Radio regarding the Russian proposal that it is “not yet time to pop the champagne.”