US President Barack Obama has "underscored the necessity of Hamas ending rocket fire into Israel" in a telephone call to the Egyptian President Mohamed Morsi, the White House said.
Obama also expressed regret for the deaths of Israeli and Palestinian civilians in calls with both Morsi and Israeli Prime Minister Benjamin Netanyahu.
Today's bombing in Tel Aviv is reminiscent of six years ago and could mark a serious escalation in the conflict.
A truce in Gaza suits all sides but none of the groups seem interested in a long-lasting solution.
A complex system of air defences has been instrumental in protecting Israel's population from incoming rockets.