Israel’s military withdrew Sunday from a key corridor dividing the Gaza Strip, leaving nearly all of the territory’s north, as required by a tenuous cease-fire with Hamas ahead of any negotiations for a longer-lasting agreement.

The military’s departure from the Netzarim Corridor in Gaza came as the Israeli government sent a delegation to Qatar over the weekend to discuss the next group of Israeli hostages and Palestinian prisoners to be freed during the cease-fire agreement’s initial phase, which went into effect last month and is ongoing.

The gaunt appearances of three Israeli hostages who were released on Saturday, stoking public comparisons to Holocaust victims, heaped new pressure on the negotiations.

In a statement on Sunday, the Israeli military said troops were “implementing the agreement” to leave the corridor and allow hundreds of thousands of Palestinians to continue returning home to northern Gaza.

Two Israeli military officials and a soldier in Gaza who were not authorized to discuss the situation publicly or by name said the troops had already left the Netzarim Corridor by Sunday morning.

Hamas also said that Israeli troops had left the zone, saying in a statement that it was “a victory for the will of our people.”

Sunday’s withdrawal from the corridor means that the presence of Israeli troops in Gaza is now mostly limited to a small sliver of land in southern Gaza, near the Egyptian border, and a buffer zone along the Israeli border.

Gaza’s interior ministry alerted Palestinians heading north on Sunday that their vehicles could still be inspected by foreign security contractors there to prevent weapons from being transferred from the south.

“We call on citizens to be careful and adhere to moving according to the currently permitted mechanism for their safety,” the interior ministry said Sunday in a statement.

The Israeli military had ordered a mass evacuation of northern Gaza in the early days of the war and patrolled the corridor, in part to prevent Palestinians from returning. Israeli troops had already partly withdrawn from the Netzarim Corridor last month, leaving the foreign contractors to fill the void.

Their complete withdrawal from the corridor was required under the first 42-day phase of the cease-fire deal — which is now at the halfway point — and necessary to advance to its next stage to end the war in Gaza fully.

Significant new pitfalls to reaching an agreement for the next phase — which could involve a complete Israeli military withdrawal from all of Gaza — emerged over the past week, however, after President Trump said that the United States could take over Gaza and turn it into the “Rivera of the Middle East” by relocating its Palestinian residents.

On Sunday, Saudi Arabia’s foreign ministry again rejected the proposal, repeating that no lasting peace agreement could be reached without creating a sovereign Palestinian state — a diplomatic goal for generations, but one that officials and experts now say is probably all but impossible to achieve.

Egypt’s foreign ministry said on Sunday that it would host an emergency Arab summit late this month in Cairo “to address the new and dangerous developments in the Palestinian cause,” noting that the meeting was being coordinated with high level officials in Arab nations and had been scheduled at the request of Palestinian officials.

The emaciated appearance of three Israeli hostages who were freed by Hamas on Saturday has also spurred widespread concern in Israel that its prime minister, Benjamin Netanyahu, has not acted quickly enough to ensure their or others’ release — increasing the pressure on the Israeli government to bring the rest of the captives home and advance to the second phase of a deal.

On Sunday, the family of Alon Ohel, one of the hostages still in captivity, said in a statement released by a group representing relatives of the captives, that for the first time in more than 490 days since he was captured, they received word that he is alive and that he has been held in tunnels in Gaza along with some captives who were recently freed. The statement demanded that Israeli leaders “take the necessary humanitarian steps to rescue Alon and the other victims from the hell they are experiencing.”

“Time is running out,” the statement added. “The second phase of the deal must be advanced to bring back all the hostages.”

But despite the presence of negotiators and mediators this weekend in Qatar, no progress was expected in talks concerning the next stage of the truce until Mr. Netanyahu convenes a meeting of his top security officials in the coming days.

In an interview on Saturday in Washington, where he had been meeting with the Trump administration, Mr. Netanyahu said Hamas, not he, was to blame for the hostages’ conditions. He predicted that at least a half-dozen more hostages would be released by the end of next week.

“We have three war aims in Gaza,” Mr. Netanyahu said in an interview with Fox News. “One, destroy Hamas’s military and governing capabilities. Two, get all the hostages out. Three, make sure that Gaza never poses a threat to Israel again. And I’m committed to achieving all three.”

Even as Israeli troops left the key corridor in Gaza, they continued raids and patrols in the occupied West Bank. Palestinian health officials there said at least two people, including a woman who was eight months pregnant, were killed in the Nour al-Shams refugee camp in Tulkarm. The Israeli military said that its police criminal investigation unit had begun an inquiry.

Hiba Yazbek , Gabby Sobelman and Ephrat Livni contributed reporting.