After U.S. ultimatum, Israel immediately promises to open new aid routes into Gaza

Israel promised to open new humanitarian aid routes into Gaza immediately after being threatened Thursday with an ultimatum from its most important international ally.

A border crossing into northern Gaza and an Israeli port will both be used to deliver food and aid for the first time since the Mideast conflict erupted last fall, Israel announced.

This promise to use the Erez land crossing and the Ashdod port for aid came within hours of Israel receiving an unprecedented threat from U.S. President Joe Biden.

The U.S. had warned its Middle Eastern ally to immediately adjust course in certain aspects of its war in Gaza during a half-hour phone call between Biden and Israeli Prime Minister Benjamin Netanyahu.

Israel provided no public timeline for the opening but the White House said in a statement it would be intently watching for progress: "[This] must now be fully and rapidly implemented."   

The phone call, the U.S. said earlier, was spurred by the deaths of seven aid workers, including a Canadian-American citizen, killed earlier this week in Israeli strikes.

"There's been growing frustration," with Israel's handling of the war, White House spokesman John Kirby said Thursday.

In the coming hours and days, he said, the U.S. would look for several specific changes: new humanitarian aid crossings into Gaza, an immediate ceasefire as Israel takes new steps to protect civilians, and more movement in hostage negotiations.

In an indicator of the shifting politics of the war, this marked the first time the Biden administration had threatened publicly to use its leverage on Israel to get specific changes in Gaza.

In Washington, criticism of Israel, once relegated to the fringe, has moved into the mainstream, with Biden facing particular pressure from his party's left.

What's less clear is what, exactly, the U.S. is threatening Israel with.

The White House has repeatedly refused to offer specifics on just what will happen if it remains unsatisfied with what it hears back from Netanyahu's government. 

For example, Kirby sidestepped the question of whether the U.S. would halt weapons transfers. He simply said the U.S. will adjust its policies, based on what Israel does next.

"What we want to see are some real changes on the Israeli side. And if we don't see changes from their side, there'll have to be changes from our side," he said.