The Israeli government said Friday that it will allow two fuel trucks per day to enter Gaza. But no fuel was delivered Friday due to the latest communications blackout, the United Nations Relief and Works Agency for Palestine Refugees in the Near East said.

Juliette Touma, spokeswoman for UNRWA, told ABC News that fuel has been "used as a weapon of war" since the Israel-Hamas conflict began.

“Seventy percent of people do not have clean drinking water because there is no fuel. … Sewage is starting to overflow in some parts of Gaza. It's a disaster," she said. "[We] should not be forced to beg for fuel just to be able to do our work. It's unacceptable."

UNRWA's shelters are currently housing 800,000 people, which Touma said is "way over the capacity."

"We planned for less than one quarter of what we have," she said. "And with the restrictions that we have on fuel and the little aid that has been coming in that we are not able to even collect or pick up, the situation is becoming tragic by the hour."

-ABC News' Patrick Reevell

The United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) confirmed that no fuel was delivered to the Gaza Strip on Friday due to the latest communications blackout.

The agency said it was forced to suspend its operations there after telecommunications companies ran out of generator fuel, plunging the war-torn territory into another blackout on Thursday afternoon.

"We are unable to operate due to the lack of communications," an UNRWA spokesperson told ABC News in a statement on Friday afternoon. "We have no communications with Gaza. Transport of aid trucks, water desalination and pumping and sewage treatment activities have been halted."

-ABC News' Ayat Al-Tawy and Zoe Magee

The Israeli government announced Friday that it will allow two fuel trucks per day to enter the war-torn Gaza Strip.

The Israeli War Cabinet said in a statement that it has "unanimously approved a joint recommendation" of the Israel Defense Force and Israel's Shin Bet internal security agency "to comply with the U.S. request and allow the entry of two diesel tankers a day for the needs of the U.N. to support water and sewer infrastructure."

The trucks will pass through the Egyptian-controlled Rafah border crossing with the help of the United Nations, delivering the fuel to civilians in southern Gaza, "provided that it does not reach Hamas," according to the Israeli War Cabinet.

"This action allows Israel the continued international maneuvering space necessary to eliminate Hamas," the cabinet said. "This action is intended, among other things, to minimally support water, sewage and sanitation systems, in order to prevent the outbreak of epidemics that could spread throughout the entire area, harm both the residents of the Strip and our forces, and spread even into Israel."

The U.S. has been urgently pressuring Israel to allow fuel into Gaza over the last few days, with Secretary of State Antony Blinken calling multiple members of the Israeli war cabinet to warn them that failure to move quickly on this would certainly result in a humanitarian catastrophe, according to a senior State Department official.

Blinken told the Israeli officials that fuel had to be separate from hostage negotiations, the official said.

The official said the U.S. will continue to push for the amount of fuel allowed in to be steadily increased.

-ABC News' Jordana Miller and Shannon Crawford

Negotiations for a hostage deal with Hamas are still ongoing, Israeli and U.S. sources told ABC News on Friday.

The potential agreement would involve Hamas releasing a certain number of hostages in exchange for a pause in fighting of some length of time in the Gaza Strip. But many of the details are still up in the air, according to U.S. sources.

The discussions are intense and remain fluid, according to an Israeli source. A disagreement has unfolded inside Israel’s defense cabinet with some ministers wanting to accept a deal to free about 50 women and children, while other ministers want all of the women and children as well as their family members released -- about 80 hostages in total, ABC News has learned.

Hamas, the militant group that rules Gaza, took more than 200 people hostage -- including Americans -- while carrying out an unprecedented attack on neighboring Israel on Oct. 7, according to Israeli and U.S. authorities.

-ABC News' Shannon Crawford and Matt Gutman

The Rafah border crossing between Gaza and Egypt opened again on Monday, permitting 559 foreign passport holders as well as Egyptians to cross through to Egypt, a Rafah border crossing official said.

Four injured or sick Palestinians and five of their family members also crossed into Egypt, the official said.