Biden to Netanyahu: Protect civilians in Gaza or US policy will change

President Joe Biden threatened on Thursday to condition support for Israel's offensive in Gaza on it taking concrete steps to protect aid workers and civilians, seeking for the first time to leverage U.S. aid to influence Israeli military behavior.

Biden's warning, relayed in a call with Prime Minister Benjamin Netanyahu on Thursday, followed a deadly Israeli attack on World Central Kitchen aid workers that spurred new calls from Biden's fellow Democrats to place conditions on U.S. aid to Israel. Israel said the attack was a mistake.