Israel delayed a cabinet vote on the cease-fire deal in Gaza after Prime Minister Benjamin Netanyahu accused Hamas of reneging on parts of the agreement, underscoring the pact’s fragility as mediators worked to iron out the wrinkles ahead of its implementation on Sunday.

President Biden and the prime minister of Qatar announced Wednesday both Israel and Hamas had accepted the truce, the result of a year of painstaking diplomacy that reached a conclusion in the days before Donald Trump ’s inauguration as president.

Palestinian militant group Hamas also said it had reached a deal with Israel, while Israeli President Isaac Herzog welcomed the agreement and urged the Israeli government to accept it.

But Netanyahu accused Hamas on Thursday of reneging on parts of the agreement during negotiations taking place in Qatar, creating what his office called “a last-minute crisis.”

The Israeli prime minister’s office said the cabinet, which had been expected to convene early Thursday, wouldn’t meet to vote on the deal until Israeli negotiators said Hamas had accepted all aspects of the deal.

Ezzat Al-Rishq, a senior Hamas official and member of the group’s political bureau, said Thursday that the group remained committed to the deal. Another Hamas official, Sami Abu Zuhri, told a pan-Arab satellite channel that Netanyahu’s comments were “baseless.”

One issue that arose in the talks in the Qatari capital, Doha, was the matter of Israel’s withdrawal from a strip of land on the Gaza-Egypt border known as the Philadelphi corridor. Israeli officials have said they want Israel’s forces to remain in the area longer. The text of the agreement, reviewed by The Wall Street Journal, calls on Israel to gradually reduce its forces in the area in the first of the three phases of the deal.

An Israeli official said, “Israel remains in during all of the first phase in the corridor, for all 42 days.”

And while the two sides have agreed on the hostages that would be freed from Gaza, a disagreement remains over which Palestinian prisoners Israel would release in return, the mediators said.

Hamas has again raised the release of six prominent Palestinian detainees, including political leaders Marwan Barghouti and Ahmad Saadat, mediators said. The group brought up the issue after initially agreeing to postpone discussion of it to a later phase of the deal, they added.

Hamas is making new demands that Israel won’t agree to, including regarding the list of prisoners to be released, the Israeli official said.

The negotiating teams in Doha were pushing to resolve the pending issues, Arab mediators said Thursday.

Earlier this week, negotiators—including Steve Witkoff , Trump’s designated Middle East envoy and officials from the U.S., Israel and Arab countries—convened in Doha to finalize the draft agreement.

The deal envisions multiple phases, starting with an initial release of hostages by Hamas and Palestinian prisoners by Israel along with convoys of humanitarian supplies entering Gaza. Hamas and Israel would negotiate the terms of a more lasting truce during the initial stage.

Israel launched more airstrikes in the Gaza Strip on Wednesday and Thursday morning, according to Palestinian media and residents of the enclave. WAFA, the official news agency of the Palestinian Authority, said several people had been killed in Israeli bombings in Gaza City.

The Israeli military said Thursday it had struck 50 targets across the enclave over the past day, including members of Hamas and Islamic Jihad, another militant group in Gaza, and weapons and other military facilities belonging to Palestinian armed groups. It also said it killed a Hamas member who participated in the Oct. 7, 2023, attack on Israel that sparked the current war.

Within Israel, the deal also faces resistance from far-right politicians who want Israel to stick to its original stated war aim of eliminating Hamas. Hard-line Israeli politicians such as National Security Minister Itamar Ben-Gvir and Finance Minister Bezalel Smotrich hold key positions in Netanyahu’s government and have threatened in the past to leave his cabinet if he accepts a cease-fire, risking the collapse of the ruling coalition.

Ben-Gvir on Tuesday called the agreement “terrible” and urged Smotrich to join him and “announce together clearly to the prime minister that if the deal is implemented we will both quit the government.”

Groups of right-wing protesters who oppose the deal took to the streets of Jerusalem on Thursday, with dozens blocking roads and holding signs that read, “Yes to victory, no to surrender!” Protests in recent days against the deal have drawn hundreds of activists.

If it is fully implemented, the deal could mark the beginning of the end of one of the deadliest episodes in modern Middle East history. The war has killed more than 46,000 Palestinians in Gaza and hundreds of Israeli soldiers, leaving much of the enclave in ruins.

Israel launched its offensive in Gaza in response to the Hamas-led attack in southern Israel that killed around 1,200 people. Palestinian militants seized another 250 hostages, setting in motion a painful ordeal for hundreds of the captives’ families who have campaigned for their release.

A cease-fire in Gaza could also calm tensions across the region after the conflict in the strip ignited wider hostilities, including a war between Israel and Hezbollah in Lebanon and the first-ever exchanges of direct fire between Israel and Iran last year.

—Saleh al-Batati contributed to this article.

Write to Summer Said at summer.said@wsj.com , Jared Malsin at jared.malsin@wsj.com and Anat Peled at anat.peled@wsj.com