Israel’s Knesset narrowly endorsed the Islamabad ceasefire framework and its 90-day inspection extension by a vote of 64 to 56 on Tuesday evening, with the 12 seats of Benny Gantz’s centrist National Unity bloc supplying the margin that kept Prime Minister Benjamin Netanyahu’s government intact and cleared the diplomatic runway for the postwar donor conference opening in Marseille on Wednesday.

The vote, taken after a 14-hour debate that stretched past midnight in Jerusalem, ratified the verification protocols negotiated in Doha last week as binding on the Israeli government and authorized the foreign ministry to “execute the obligations of the framework in good faith.” It is the first time the full Knesset has formally weighed in on any element of the postwar architecture, and it converts a coalition-by-arithmetic into something closer to a parliamentary mandate at the moment Mr. Netanyahu most needed it.

Mr. Gantz, who has spent the past nine days negotiating the terms of his bloc’s external support, told the chamber that his lawmakers were “voting for the country, not for the prime minister.” He added that National Unity reserved the right to withdraw its support “the moment the framework is used as cover for a quiet retreat from any of Israel’s red lines,” a phrase aides confirmed had been added to his speech in the final hour of drafting.

The motion was tabled by Foreign Minister Israel Katz under emergency procedures after the Otzma Yehudit and Religious Zionism factions tried twice on Monday to force a no-confidence vote that would have collapsed the government before Marseille. Both motions failed on procedural grounds, but they made plain that the prime minister’s 61-seat coalition could not survive a substantive test on its own. Mr. Gantz’s intervention, telegraphed in television interviews over the weekend, supplied the floor that the government’s own benches could not.

In Marseille, French diplomats reacted with cautious satisfaction. President Emmanuel Macron’s office said in a statement issued shortly after the result that the vote “removes the last political question mark over the Israeli delegation” and confirms that the foreign minister would lead a full Israeli team to the Palais du Pharo. Conference co-chair Italy issued a parallel statement welcoming “a stabilizing signal from Jerusalem at exactly the right moment.”

“The Israelis arrive in Marseille tomorrow with a piece of paper in their pocket that says the parliament voted for the framework,” said Layla Hassan, a Beirut-based regional analyst at the Levant Policy Center. “That paper changes the conversation. Gulf donors who were quietly asking whether their commitments would survive an Israeli election can now stop asking. The mediators got the calendar they paid for.”

The two hours of voting were preceded by what Israeli commentators called the sharpest exchanges in the Knesset since the war’s outbreak. National Security Minister Itamar Ben-Gvir, who resigned from the cabinet on April 27 over the same framework, accused Mr. Netanyahu from the opposition benches of “renting his majority from a man who refused to serve in his war cabinet.” Mr. Eliyahu, the former heritage minister, called the inspection regime “an Iranian flag flown over our nuclear policy.” Both men’s parties voted no in unison with the Joint List and three defectors from the prime minister’s own Likud, producing the 56-vote opposition tally.

Mr. Netanyahu, speaking from the rostrum shortly before the vote, made an explicit appeal across the aisle that was unusual by Israeli standards. He thanked Mr. Gantz by name “for placing the state above the parties” and said the framework “protects Israel’s deepest interests while giving our soldiers, our communities and our economy the time they need.” He stopped short of committing to early elections, telling lawmakers that the question of “when the country goes to the polls” would be answered “when the work of stabilization is done.”

The arithmetic of survival, however, was not the only message. Aides to Mr. Gantz briefed Israeli reporters after the vote that National Unity would now demand, in exchange for continued external support, monthly written briefings to a Knesset subcommittee on the operationalization of the inspection regime, and a binding commitment from the prime minister not to seek any changes to the framework without a fresh parliamentary vote. A senior official in Mr. Netanyahu’s office, granted anonymity to describe internal deliberations, said the prime minister had agreed in principle to both demands during a Sunday meeting at the official residence and would formalize them in writing this week.

In Washington, President Donald Trump welcomed the vote in remarks to reporters as he boarded Marine One for a weekend trip to Mar-a-Lago, calling Mr. Netanyahu “a survivor, a true survivor, the greatest survivor maybe ever.” Asked whether the United States would now commit additional reconstruction funds at the Marseille conference, the president said the figure was “going to be very fair, very strong” and declined to elaborate. A State Department official briefed on the U.S. delegation’s portfolio said Secretary of State Marco Rubio would arrive in Marseille on Wednesday morning with “a pledge in the high single-digit billions” and authority to add to it as the conference progressed.

Iranian officials greeted the vote with what one Tehran-based diplomat described as “studied indifference.” Foreign Ministry spokesman Esmail Baghaei told the state news agency IRNA that “the internal contortions of the occupying regime are not Iran’s concern, but the obligations the regime has now formally undertaken are very much Iran’s concern, and we will measure them by deeds, not by Knesset arithmetic.” Iranian Foreign Minister Abbas Araghchi, who arrived in Marseille on Tuesday afternoon, made no public remarks on the vote, but a senior Iranian official traveling with the delegation said Tehran had taken note that “the Israeli parliament has accepted, at last, what the Iranian parliament accepted three weeks ago.”

The vote was watched closely in Arab capitals whose pledging delegations are due to land in Marseille on Wednesday morning. Saudi Foreign Minister Prince Faisal bin Farhan, in a brief stop at Riyadh’s King Khalid International Airport before departing, told reporters that “the Knesset vote is a welcome ratification” and that the Gulf Cooperation Council would arrive at the conference with a “consolidated, credible offer” for Iran, Iraq and Yemen. The United Arab Emirates, Qatar, Kuwait and Bahrain are expected to coordinate their pledges through a single GCC envelope worth, according to one Gulf official briefed on the figures, “between 18 and 22 billion dollars over five years.”

Mr. Gantz, in a final remark from the floor that drew applause from his own benches and silence from the prime minister’s, said the framework was “not a victory for any party in this chamber, including mine.” He added that he expected the next 90 days to be “the most consequential of the postwar period” and that National Unity’s continued support would be reassessed “at the end of every one of them.” Officials said the first of the agreed monthly Knesset briefings would be scheduled for early June, after the framework’s inaugural Natanz inspection visit and the close of the Marseille pledging window.