Updated November 23, 2023 at 3:11 PM ET

TEL AVIV, Israel — A deal to pause the fighting in Gaza and exchange Israeli hostages for Palestinian prisoners — originally expected to start on Thursday — will instead begin early Friday morning, according to the foreign ministry in Qatar, where the deal was negotiated.

The new start time for the anticipated four-day pause in the fighting would be 7 a.m. local time, according to a spokesperson for the foreign ministry in Qatar. The first group of 13 Israeli hostages — all women and minors — are expected to be handed over by Hamas after 4 p.m. local time, with Israel releasing Palestinians at that time, the foreign ministry said.

Prime Minister Benjamin Netanyahu's office did not immediately confirm the new start time, but issued a statement saying it had received an "initial" list of hostage names. "The relevant officials are checking the details of the list and are currently in contact with all families," it said.

Later, a spokesperson for Israel's military cautioned that the deal could still fall through "and even during the process there may be changes all the time."

"Hamas will try to take advantage of the deal and the days of a lull in fighting, by creating fear and spreading disinformation and using manipulation," the spokesperson said, adding that the deal "is not the end of the process of returning the abducted, but the beginning."

Hamas' military wing said in a statement that Israel was expected to free three Palestinian prisoners in exchange for each Israeli that's freed from Gaza.

The agreement calls for a total of at least 50 Israelis and 150 Palestinians to be freed over the four-day period, although Israel says that timeframe could be extended, with more releases on both sides, up to 10 days.

The deal also allows for 200 humanitarian aid trucks to enter Gaza each day, according to Hamas.

Egypt, which was also a party to the negotiations, announced the same revised date and time for the implementation as Qatar and Hamas did.

The temporary cease-fire and hostages-for-prisoners swap had been expected to go into effect on Thursday, but a few hours after midnight, it was suddenly put on hold. Hours after Prime Minister Benjamin Netanyahu spoke in a televised, late-evening media briefing where he discussed the agreement, Israel's National Security Adviser Tzachi Hanegbi said the temporary cease-fire was still on track "according to the original agreement," but that it wouldn't occur before Friday.

The reason for the delay was not immediately clear, but Israel's Channel 12 quoted an unnamed Israeli political official as saying "the delay isn't substantive, but technical."

The pause in fighting comes more than six weeks after roughly 240 Israeli hostages were seized by Hamas fighters in Gaza during a deadly Oct. 7 attack on Israel. The temporary truce is also meant to allow badly needed fuel and food trucks into Gaza, which has been bombarded by Israeli forces since the start of the conflict. The terms of the agreement allow for it to be extended up to 10 days if Hamas continues releasing hostages.

But the delicate nature of the deal and how it will be implemented was highlighted by Netanyahu during his Wednesday briefing. Reading from what he said was part of the temporary cease-fire agreement, the prime minister said that the International Committee of the Red Cross (ICRC) "will be allowed to visit the rest of the hostages and provide them with necessary medicines."

"I expect them to do their job," he added.

But the ICRC's spokesperson in Jerusalem, Sarah Davies, told NPR that the group was "not made aware of any agreement reached by both parties" related to such visits. "Should visits be agreed upon, the ICRC stands ready" to conduct them, Davies said, adding that the aid group "does not take part in the negotiations between the parties to the conflict."

In a statement issued later, the ICRC said it "welcomes any respite from the fighting and bombardment in Gaza," adding that "everything possible must be done to scale humanitarian aid during this pause."

"Israel should immediately allow for the permanent resumption of sufficient fuel, water and electricity supplies, without which humanitarian needs will continue to deepen," the Red Cross said.

Meanwhile, the Hamas-controlled Gaza Health Ministry says that Israeli troops arrested the director of the Al-Shifa Medical Hospital Complex, Dr. Muhammad Abu Salamiya, on Thursday. Salamiya was traveling with a U.N. World Health Organization convoy that was stopped at an Israeli checkpoint, the health ministry says, and as a result, it has decided "to stop coordination with the World Health Organization on the issue of evacuating the remaining wounded and medical teams until a report is submitted explaining what happened and the detainees are released."

The Israel Defense Forces and the Israeli Security Agency (ISA) issued a statement about the arrest, acknowledging that Salamiya had been taken into custody and "transferred for ISA questioning." It said that Al-Shifa, "under his direct management, served as a Hamas command and control center," adding that the Hamas tunnels utilized hospital electricity and resources and that Hamas stored weapons there. "Furthermore, after the Hamas massacre on October 7th, Hamas terrorists sought refuge within the hospital, some of them taking hostages from Israel with them," it said.

Salamiya's arrest comes a day after Israel's military released a video of what it said was an extensive tunnel network below the hospital, complete with toilets, sleeping quarters and air conditioning. The army, which laid siege to the hospital, says the facility, Gaza's largest hospital, was used as a covert Hamas command center.

Scott Neuman reported from Tel Aviv and Lauren Frayer reported from Ramallah, in the Israeli-occupied West Bank.

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