Prime Minister Benjamin Netanyahu says the military will intensify its offensive in Gaza after Hamas militants rejected a cease-fire proposal and continued firing rockets into Israel.
Netanyahu said Tuesday he would have preferred to solve the conflict "diplomatically," but actions by Hamas leave "no choice but to expand and intensify the campaign against it."
The Israeli military held fire for six hours after agreeing to an Egyptian cease-fire proposal Tuesday. But Israel says it resumed airstrikes after Gaza militants fired about 50 rockets over Israel from Hamas-controlled territory.
An Israeli citizen was killed by rocket fire Tuesday near the Erez crossing into Gaza, the first Israeli casualty since the offensive began last week. Palestinian health officials say 194 Palestinians have died in the latest conflict to date.
The small number of Israeli casualties is attributed in large part to its new Iron Dome missile defense system, which has intercepted rockets above several Israeli cities.
White House spokesman Josh Earnest says the U.S. "is concerned about any innocent civilians who are injured or killed" and believes "there have been far too many innocent civilians who have lost their lives as a result of the violence and conflict in that region."
He stressed that rocket fire launched from Hamas and other groups "needs to stop."
Israeli Foreign Minister Avigdor Lieberman defended his country's right to defend itself during a visit to a rocket-hit town with his Italian counterpart.
"We understand that we're still in the midst of the battles. They still continue with the launching, and Hamas is aiming only [at the] civilian population. And you can imagine if this is to happen in every country. Can you imagine rockets on Roma or Napoli? Can somebody imagine rockets on Washington or New York? And I think that we must retaliate," said Lieberman.
Earlier, U.S. Secretary of State John Kerry rebuked Hamas for so far refusing to de-escalate the violence.
"I cannot condemn strongly enough the actions of Hamas in so brazenly firing rockets, in multiple numbers, in the face of a goodwill effort to offer a cease-fire in which Egypt and Israel joined together and the international community strongly supports the idea of a cease-fire, the need, the compelling need to have a cease-fire," said Kerry.
Some Hamas officials had signaled the group had not made a decision Tuesday, but its armed wing says it had rejected the Egyptian plan, which they say would amount to "surrender."
The proposal called for a temporary cease-fire to go into effect Tuesday, followed by the opening of Gaza's border crossings and talks between the two sides in Cairo within two days.
Israel launched its offensive last Tuesday in response to what it said was weeks of heavy rocket fire out of Hamas-ruled Gaza.
Egypt, the first Arab state to reach peace with Israel, often serves as a mediator between Israel and Hamas. In 2012 fighting between Israel and Hamas, Egypt's then-president Mohamed Morsi brokered a cease-fire.
Some information for this report provided by Reuters, AFP and AP.