Washington —  Secretary of State Antony Blinken said on Sunday that the U.S. "will not support" an Israeli military operation in the southern city of Rafah without a "credible plan to protect civilians."

"From day one, President Biden has been determined to support Israel in defending itself and trying to make sure that Oct. 7 never happens again," Blinken said on "Face the Nation" on Sunday. "At the same time, he's been very clear that in doing that it's imperative that Israel protect civilians and make sure that humanitarian assistance gets to those who need it."

• Transcript: Secretary of State Antony Blinken on "Face the Nation," May 12, 2024

The comments come as Israel has prepared to expand its military operation in Rafah in recent days despite international criticism, ordering new evacuations for civilians in the densely populated area Saturday. Meanwhile, continued support from the U.S. for Israel has been thrown into question. 

President Biden said on CNN last week that the U.S. had paused a shipment of bombs to Israel, warning that "civilians have been killed as a consequence of those bombs" as a major operation in the southern city of Rafah, considered the last refuge in the Gaza Strip, appeared imminent. Blinken clarified Sunday that the only thing that the administration has held back are high-payload bombs given the impact they could have on highly populated areas.  

The president, who has already been criticized on the left for his continued support for Israel, has faced intense pushback over this move from the right, accused by some of falling short in his commitment to Israel. But Blinken defended the president on Sunday, saying "no president has done more to defend Israel when it really mattered than Joe Biden." But he added that the administration has been "very clear for many months now about our concerns about a major military operation in Rafah."

"What we've been clear about is that if Israel launches this major military operation into Rafah, then there are certain systems that we're not going to be supporting and supplying for that operation," Blinken said.

The secretary also made clear that the U.S. has been looking to develop a plan for what happens after the conflict in Gaza is over. He noted that Hamas is coming back in parts of Gaza that Israel has cleared. And even if Israel has initial success in Rafah, Blinken noted that it may not be sustainable. 

The comments come after Blinken delivered a report to Congress on Friday on the Israeli military's operations in Gaza that said it is "reasonable to assess" that Israel violated international humanitarian law. But the report stopped short of formally finding that the Israeli military had already done so.

The highly anticipated report noted that although there are allegations that Israel violated international humanitarian law, there isn't "complete information" about whether U.S. weapons were used. 

"We're looking at the totality of what's happened," Blinken said Sunday. "We think it's reasonable to assess based on what's happened that there have been acts that have been inconsistent with Israel's obligations under international law, but we haven't drawn definitive conclusions."

The Biden administration has faced criticism from both the left and right since the report's release, as some Republicans have decried its criticism of Israel while some Democrats have argued that the report doesn't go far enough. 

Appearing on "Face the Nation" on Sunday, Sen. Tom Cotton, an Arkansas Republican and vocal critic of the Biden administration, said the report "doesn't make any sense at all," adding that it sounds like "mealy-mouthed politics."

Sen. Chris Van Hollen, a Maryland Democrat who also appeared on "Face the Nation," said that while he appreciated the administration's assessment, the report did "duck the hard questions."

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Kaia Hubbard

Kaia Hubbard is a politics reporter for CBS News Digital based in Washington, D.C.

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