The first step to bringing peace to Gaza is a de-escalation of violence because that would "create space for something deeper," U.S. State Department spokeswoman Victoria Nuland said hours before Secretary of State Hillary Clinton lands in Jerusalem.

Israel has said a ceasefire agreement with Hamas would have to be contingent on a 24-hour calming of violence. The framework of a broader ceasefire deal might include opening up some borders in Gaza, loosening Israel's blockade of the occupied territory.