This was debunked by Israel:
http://www.haaretz.com/hasen/spages/738315.html
Responding to a report in a pan-Arab daily newspaper that Israel presented Damascus with an ultimatum, an Israel Defense Forces officer said Saturday that targeting Syria is currently not on Israel's agenda.
"We're not a gang that shoots in every direction," the officer said. "It won't be right to bring Syria into the campaign."