House Speaker Mike Johnson and Majority Leader Steve Scalise have publicly accused the Biden administration of withholding aid to Israel following reports that some aid shipments have been halted. Johnson said that the Biden administration as recently as Friday had assured his staff that there would be "no delay" in assistance to Israel.

Johnson said he received a report this morning from on the ground in Israel that said "a shipload of munitions and precision weapons, which are to be used to help protect civilians and Rafah, is being withheld."

In a letter to President Joe Biden, Senate Republicans Jodi Ernst and Ted Budd said they are "shocked" and "deeply concerned" that the Biden administration failed to notify Congress before withholding ammunition to Israel.

"If these reports are true, then you have once again broken your promise to an American ally," they said.

-ABC News' Lauren Peller and Shannon Crawford

In his first comments since Israel's offensive into Rafah began, Prime Minister Benjamin Netanyahu said that Hamas' cease-fire proposal on Monday was "intended to torpedo the entry of our forces into Rafah."

"It did not happen. As the War Cabinet unanimously determined, the Hamas proposal is very far from Israel's necessary requirements," Netanyahu said.

"I instructed the working-level delegation that went to Cairo: continue to stand firm on the conditions necessary for the release of our abductees, continue to stand firm on the essential requirements for guaranteeing Israel's security," Netanyahu said.

-ABC News' Will Gretsky

Israeli tanks controlled Gaza's Rafah border crossing early Tuesday, as military officials accused Hamas of using the crossing for "terrorist purposes."

"Following intelligence that indicated that the Rafah Crossing in eastern Rafah was being used for terrorist purposes, IDF troops managed to establish operational control of the Gazan side of the crossing," Israel Defense Forces officials said in a statement.

Mortars had on Sunday been fired "from the area," killing four IDF soldiers, the Israeli military said.

A video and photos taken by the Israeli military and released Tuesday appeared to show several Israeli tanks operating on the Gazan side of the border.

-ABC News' Kevin Shalvey

The Israeli military moved into eastern Rafah late Monday to begin a "precise counterterrorism operation" targeting Hamas, the Israel Defense Forces said Tuesday.

IDF troops also took "operational control" of the Gazan side of the border crossing between Gaza and Egypt, officials said in a statement.

The operation in Rafah overnight included air strikes and on-the-ground troops, the military said. About 20 "terrorists" were killed and three tunnels were located, IDF officials said.

"IDF ground troops are continuing to operate against Hamas terrorist operatives and infrastructure in the area of the Rafah Crossing in eastern Rafah," the statement said.

-ABC News' Jordana Miller, Jessica Gorman and Kevin Shalvey

The U.N. Agency for Palestine Refugees said Monday it wouldn't begin to evacuate its staff from Rafah, adding that a possible Israeli invasion into the refugee city would be "devastating."

"UNRWA is not evacuating: the Agency will maintain a presence in Rafah as long as possible & will continue providing lifesaving aid to people," the group said in a statement.

An invasion into the city "would mean more civilian suffering & deaths," the agency said.

-ABC News' Kevin Shalvey