American intelligence estimates indicated that Hamas still possesses enough ammunition to strike Israel for several months to come, in a recent report published by the Wall Street Journal.

The newspaper quoted Israeli officials as saying that despite the air and ground campaign in Gaza, the goal of destroying Hamas has not been achieved.

The newspaper's report said that Israeli forces killed between 20 percent and 30 percent of Hamas fighters, according to estimates by US intelligence agencies, a toll that is less than Israel's goal of destroying the movement.

A senior Israeli military official said of Hamas' goal: "You don't have to win, all you have to do is not lose."