The United States on Wednesday offered support for Israel's assault on the Gaza Strip, blamed Hamas for the incursion, and urged the Palestinian militant group to free a captured Israeli soldier.
President George W Bush's spokesman Tony Snow did however call on Israeli forces to safeguard civilian life after Israeli Prime Minister Ehud Olmert vowed to use "extreme means" to free the teenaged conscript Gilad Shalit.
"Israel has the right to defend itself and the lives of its citizens," Snow told reporters.
"The hostage-taking and the attacks by Hamas last weekend have precipitated the current events in Gaza," he said. "As we have said since the attack, Hamas should release and return the kidnapped Israeli soldier immediately.
The offensive, which plunged much of Gaza into darkness after Israeli jets targeted a power station, is Israel's first since pulling its troops out of the enclave last year, ending a 38-year occupation.
"In any actions the government of Israel may undertake, the United States urges that it ensures that innocent civilians are not harmed and also that it avoid the unnecessary destruction of property and infrastructure," Snow said.
The US comments came after Israel massed troops around Gaza airport and launched air strikes against a site Palestinian sources said was a training ground for militants from the armed wing of Hamas.