Israeli forces took over the Rafah crossing between Egypt and Gaza after capturing the Palestinian side of the strategic site on Monday night, according to Palestinian and Israeli officials.

Why it matters: The Rafah crossing is one of the main delivery routes for humanitarian assistance to Gazans. The United Nations Relief and Works Agency for Palestine refugees (UNRWA) warned on Tuesday that its closure is jeopardizing aid for refugees in the enclave.

• More than one million displaced Palestinians are sheltering in the southern Gaza city.

Driving the news: "Continued interruption of the entry of aid and fuel supplies at the Rafah crossing will halt the critical humanitarian response across the Gaza Strip," UNRWA said in a post on X.

• UNRWA claimed that the disruption in the Rafah crossing could also have consequences for northern Gaza, which a UN-backed body warned in March was at risk of famine. USAID director Samantha Power said last month that famine had already begun.
• "The catastrophic hunger faced by people especially in northern Gaza will get much worse if these supply routes are interrupted," UNRWA added.
• Israeli officials said the capture of the Rafah crossing won't have an effect on northern Gaza, which gets most of its aid from the Erez crossing on the northern border between Gaza and Israel. That crossing reopened last week for the first time since it was attacked by Hamas on Oct. 7.

Zoom in: IDF Spokesperson Lt. Colonel Nadav Shoshani told reporters on Tuesday that IDF troops took control of the Rafah crossing. Special forces were carrying out scans in the area, he added.

• "IDF forces captured the Palestinian side of the Rafah crossing following intelligence that indicated that it was being used for terrorist purposes by Hamas," Shoshani said.
• IDF ground troops are continuing to operate against Hamas operatives and infrastructure in eastern Rafah, he said.

Behind the scenes: Rafah crossing came up during the phone call between president Biden and Israeli Prime Minister Benjamin Netanyahu on Monday ahead of the IDF operation, Israeli and U.S. officials said.

• Biden told Netanyahu that because the Rafah crossing will be closed for entry of aid, Israel must open the nearby Kerem Shalom crossing between Israel and Gaza immediately.
• The White House said in a statement that Netanyahu committed to do so.
• U.S. and Israeli officials said they expect the Kerem Shalom crossing to be opened on Wednesday and process the aid trucks from Egypt that used to pass through the Rafah crossing.
• The IDF general in charge of the humanitarian situation in Gaza was supposed to travel to Washington this week, two Israeli officials said, but canceled his trip in order to be on the ground during the operation.
• One of the Israeli officials said the plan is to reopen the Rafah crossing as soon as possible, after the IDF finishes "cleaning up" Hamas presence in the area.

Zoom out: The relationship between the Biden administration and Netanyahu's government has become increasingly strained over the past few months. Israel's plans for Rafah have been a particular point of tension.

• Biden has been under immense political pressure from young prospective voters and Democrats in Congress over his support for Israel.
• Earlier this week, a group of 90 House Democrats urged Biden to consider halting sales of offensive weaponry to Israel over continued disruptions to humanitarian aid to Gaza.

Go deeper: Rafah assault threatens to be Israel breaking point for Democrats