As political fallout mounts over the Israeli airstrike that killed seven World Central Kitchen workers in Gaza this week, President Joe Biden warned Israeli Prime Minister Benjamin Netanyahu on Thursday that the U.S. is considering changing its policy toward Israel if the country does not take concrete steps toward reducing civilian casualties and addressing the looming famine in Gaza. 

“If we don’t see changes from their side, there will have to be changes from our side,” White House national security spokesperson John Kirby told reporters after the Biden-Netanyahu call. Secretary of State Tony Blinken used the same language at a press conference in Brussels, demonstrating the unified front from the administration on this shift in rhetoric.

On the call, Biden “made clear the need for Israel to announce and implement a series of specific, concrete, and measurable steps to address civilian harm, humanitarian suffering, and the safety of aid workers,” according to a White House readout of the call. Biden told Netanyahu that U.S. policy “will be determined by our assessment of Israel’s immediate action on these steps.” He also called for an “immediate ceasefire,” and urged Netanyahu to “conclude a deal without delay” to bring the hostages home.

The new language from across the Biden administration represents a shift in the White House’s posture toward Israel and the Netanyahu government as it mounts a war against Hamas in Gaza. Until now, the White House — while critical of the death toll in Gaza and the deteriorating humanitarian conditions — has said that changing U.S. policy toward Israel is off the table.

Kirby declined to offer details on what steps the White House would consider taking if Israel does not address the humanitarian crisis in Gaza. But Israel’s changes must begin “in the coming hours and days,” said Kirby. 

Israel took responsibility for the attack on the World Central Kitchen convoy and announced an investigation. After an initial assessment, IDF Chief of Staff Herzi Halevi called the attack “a mistake that followed a misidentification, at night, during a war, in very complex conditions. It shouldn’t have happened.” WCK founder Chef Jose Andres called for an independent investigation into the attack, claiming, without offering evidence, that it was a deliberate attack. (Kirby pointed out that the Israelis “have said themselves publicly after a preliminary investigation that there was no deliberate targeting of WCK.”)

The White House made clear that Israel should not wait for the results of an investigation before taking action to change course in Gaza.

“We want to see that even as the Israelis work through their investigation, that they are willing and able to take practical, immediate steps to protect aid workers on the ground and to demonstrate that they have that civilian harm mitigation in place,” said Kirby. 

“There’s been growing frustration,” he added, that previous messages to Netanyahu about mitigating civilian harm had not gotten through to the Israeli prime minister. 

Despite Biden’s demands that Israel change course in Gaza, the White House reaffirmed Washington’s “ironclad” support for Israel as it faces a variety of threats.

“Israel is an ally and a friend and a partner, and the president believes strongly and has for his entire public career [in] the security of the Israeli people and the longevity of the Israeli state. and that’s not gonna change,” Kirby said. “I can say unequivocally, and I don’t think the prime minister would mind me saying here, that in the call today the prime minister reiterated his thanks to President Biden and his administration for the support that we have continued to provide Israel.”

“Israel still has a lot of threats it faces,” added Kirby. “We’re all focused on Hamas, and I understand that. They still face active threats throughout the region, including from Iran, and the United States still has an ironclad commitment to help Israel with its self-defense.”