(NewsNation) — U.S. President Joe Biden and Israeli Prime Minister Benjamin Netanyahu spoke over the phone Monday amid concerns that a ground invasion of the southern Gaza city of Rafah could begin soon.

According to a readout of the call, Biden “reiterated his clear position on Rafah.” Biden has previously told Netanyahu several times that Israeli forces should not invade the region without a credible plan to protect civilians and humanitarian aid.

“We cannot and will not speak for IDF operations,” White House national security communications adviser John Kirby said at an afternoon press briefing, adding that the U.S. made its views clear during the conversation with Israel’s prime minister.

The president also “reaffirmed his message on Yom HaShoah, Holocaust Remembrance Day” and updated Netanyahu on efforts to secure a deal to return the hostages taken by Hamas on Oct.7, according to a readout of the call.

Israel’s military Monday ordered Palestinians in areas of Rafah to start evacuating, complicating efforts by mediators to broker a deal. Still, the Associated Press reported later that day that Hamas accepted an Egyptian-Qatari cease-fire proposal.

A statement from Netanyahu’s office following Hamas’ announcement said Israel’s War Cabinet “unanimously” decided to continue the operation in Rafah.

“At the same time, although the Hamas proposal is far from Israel’s necessary requirements, Israel will send a delegation of working-class mediators to exhaust the possibility of reaching an agreement under conditions acceptable to Israel,” the statement said.

During the press briefing, Kirby said they won’t have further comment on the deal until officials review it.

Netanyahu said last week Israel’s military would enter Rafah to destroy Hamas’ battalions there “with or without a deal.”

The IDF said on X Monday afternoon that it is conducting strikes on eastern Rafah.

Axios published a report Friday stating that the Biden administration put a shipment of U.S.-made ammunition that was supposed to go to Israel on hold, the first time since Hamas’ attack that American officials have stopped a weapons delivery for the country. Israeli officials told Axios that this raised “serious concerns” for the government, sending them “scrambling to understand why the shipment was held.”

Republican Sen. Lindsey Graham of South Carolina said on X that if the report is true, it is a “foreign policy blunder,” adding that Republicans will oppose any effort to restrict weapons deliveries to Israel.

Still, the president has come under increased scrutiny from other lawmakers, even his allies in the Senate, including Bernie Sanders, I-Vt., who said the Israel-Hamas war could be Biden’s Vietnam, especially as younger voters, especially college students, call for an end to the devastation in Gaza.

“I worry very much that President Biden is putting himself in a position where he has alienated not just young people, but a lot of the Democratic base in terms of his views on Israel and this war,” Sanders said in a recent appearance on CNN.

The Department of Defense had no comment on the report other than to say “our commitment to Israel remains iron-clad.”

“The United States has surged billions of dollars in security assistance to Israel since the Oct. 7 attacks, passed the largest ever supplemental appropriation for emergency assistance to Israel, led an unprecedented coalition to defend Israel against Iranian attacks, and will continue to do what is necessary to ensure Israel can defend itself from the threats it faces,” a National Security Council spokesperson said to NewsNation. 

About 1.4 million Palestinians, which is about half of Gaza’s population, according to the Associated Press, are in Rafah. Many of them fled there from the north to escape Israel’s bombardment, which has already killed more than 34,500 people, according to the Hamas-run Gaza Health Ministry.

Those in Rafah live in densely packed tent camps or overflowing U.N. shelters or crowded apartments, the Associated Press reported, and are dependent on international aid for food, with sanitation systems and medical facilities infrastructure crippled.

“More than 200 days of war have taken an unimaginable toll on the lives of children,” UNICEF Executive Director Catherine Russell said in a statement Monday. “Rafah is now a city of children, who have nowhere safe to go in Gaza. If large-scale military operations start, not only will children be at risk from the violence, but also from chaos and panic, and at a time where their physical and mental states are already weakened.”

Warning of “a further catastrophe” for the around 600,000 children currently taking shelter in the enclave, UNICEF said they are especially vulnerable because of the “likely intensity of the violence, with potential evacuation corridors likely mined or littered with unexploded ordnance; and shelter and services in areas for relocation very likely to be limited.”

NewsNation Senior White House Producer Tanya Noury and The Associated Press contributed to this report.