It is a controversial policy, and they keep quiet about it. However, the Israeli govt has called for regime change in Syria, and also has offered military help, and medical aid, to the rebels.
Israel wants ‘butcher’ Assad ousted, Liberman says
https://www.timesofisrael.com/israel-wants-butcher-assad-ousted-liberman-says/
http://www.newsweek.com/israeli-minister-it-time-assassinate-syrias-bashar-al-assad-609848
I had not realized that two cabinet members had spoken like that.
However, both ministers reference the alleged use of chemical weapons by Assad.
So far, all the “evidence” against Assad has come from anti-Assad military groups and anti-Assad “observer” groups.
The United Nations has investigated all but one or two reports of chemical weapons.
The found traces of chemical weapons at two locations, but they could not determine which side had used them.