Two years into President Biden’s term, his aides began negotiating with Saudi leaders to have the kingdom establish diplomatic relations with Israel. But when the Israel-Hamas war began last October, the talks withered.

American and Saudi officials have tried to revive prospects for a deal by demanding more from Israel — a cease-fire in Gaza and irreversible steps toward the founding of a Palestinian nation. Now those officials say they are close to a final agreement on the main elements of what the Saudis want from the deal: a U.S.-Saudi mutual defense pact and cooperation on a civilian nuclear program in the kingdom.

Secretary of State Antony J. Blinken spoke with Crown Prince Mohammed bin Salman, the de facto Saudi leader, about these matters in private on his visit last month to Riyadh, according to the State Department. And Jake Sullivan, the White House national security adviser, is expected to follow up when he goes to Saudi Arabia and Israel this weekend.

But there are no signs that Israeli leaders are moving to join them, despite the symbolic importance for Israel of establishing ties with Saudi Arabia, the most powerful Arab nation.

That resistance, along with a potential full-scale assault by the Israeli military on the Palestinian city of Rafah, puts in jeopardy a potential three-way grand bargain that Mr. Biden envisions as the foundation to a long-term solution to the decades-old Israeli-Palestinian conflict.