The recent rescue of four hostages will likely complicate Secretary of State Antony Blinken’s efforts to broker a new cease-fire deal between Israel and Hamas that would secure the release of the remaining captives in Gaza, a senior administration official has told NBC News.

The freeing of the hostages has strengthened Israeli Prime Minister Benjamin Netanyahu’s determination to continue pursuing military operations, rather than agreeing to a cease-fire, the official told NBC News. And the Hamas military leader Yahya Sinwar, who has held out despite intense pressure for a deal from Qatar and Egypt, could take an even harder line because of the high number of civilian Palestinian casualties from the Israeli rescue operation. 

The senior official said some of the civilian victims died in the crossfire from Hamas fighters responding to the Israeli operation. A second official said Hamas is ultimately responsible for the Palestinian deaths by hiding hostages in densely populated areas.

He added that while the release of the four Israeli hostages is welcome news, it is not going to change the status quo because there is still a significant number of hostages remaining, including five Americans believed to be alive. There are also three American hostages who were killed whose families are demanding the return of their remains.  

Another complication for the diplomatic effort is Sunday’s resignation of the centrist member of Israel’s war cabinet, retired General Benny Gantz.

In resigning, Gantz accused Netanyahu of mismanaging the war and refusing to agree on what will happen to Gaza after the hostilities end. The Biden administration had tried to persuade Gantz not to quit because his absence will only strengthen Netanyahu’s ties to the far-right members of his coalition.  

On his return to the region Monday — his eighth since Hamas’ Oct. 7 attack on Israel — aides say Blinken will also focus on the desperate need to get more aid into Gaza. Israel closed access to the Rafah crossing on May 6 before it launched a new round of military operations there, making aid deliveries far too dangerous.

Egypt, Israel’s oldest Arab ally, has also been protesting against Israel’s military operations in a border area between the two countries known as the Philadelphi Corridor. All that will be part of Blinken’s agenda when he sees Egypt’s President al-Sisi Monday before going to Israel later in the day.

For the last six months, the secretary of state has been working intensively on a so-called day after plan for Israel to eventually withdraw from Gaza and turn security over to a reformed Palestinian authority, with Arab leaders promising to then help finance Gaza’s post-war reconstruction. 

But with both sides digging in against a cease-fire agreement, and outcries over the horrific death toll from this weekend’s Israeli-Hamas firefight, the chances of reaching a deal anytime soon may be fading.