israel was doing frequent bombings in syria.  in syria, controlled areas was kinda established. now, when isis are on the move,"borders" kinda changes. and if truce would not be signed, there would be risk, that during assault, isis gets some israeli bomb on their heads, which was aimed at assad forces. that might be one of reasons, why isis decided to start offensive now. a) assad forces depleated of weapons (given to hezbollah) b) israeli will not bomb them by mistake
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