Iranian officials have told U.S. counterparts in meetings in a regional capital that Tehran is willing not to retaliate over the killing of Hamas chief Ismail Haniyeh in Tehran should the war on Gaza stop, a senior source said.

The Iranians also said that the Lebanon and Yemen fronts against Israel would be deactivated, the source told Kuwait’s al-Anbaa newspaper.

Hamas appeared to push back against resuming negotiations on Thursday on any new cease-fire proposals.

In a statement, it urged mediators United States, Egypt and Qatar to submit a plan to implement what was agreed on last month, based on U.S. President Joe Biden's proposal, "instead of going to more rounds of negotiations or new proposals that provide cover for the occupation's aggression."

U.S. Defense Secretary Lloyd Austin has ordered a guided missile submarine to the Middle East and is telling the USS Abraham Lincoln aircraft carrier strike group to sail more quickly to the area, the Defense Department said Sunday.

The moves come as the U.S. and other allies push for Israel and Hamas to achieve a cease-fire agreement that could help calm soaring tensions in the region following the assassination of Hamas political leader Ismail Haniyeh in Tehran and a senior Hezbollah commander in Beirut.

The European Union’s top diplomat says it should consider sanctions in response to calls by Israel’s far-right national security minister to cut off aid to Gaza.

Writing on the X platform late Sunday, EU foreign policy chief Josep Borrell said the recent remarks by Itamar Ben-Gvir constitute “incitement to war crimes,” adding that “sanctions must be on our EU agenda.”

The leaders of France, Germany and Britain have endorsed calls for a cease-fire in Gaza, the return of scores of hostages held by Hamas and the “unfettered” delivery of humanitarian aid.

In a joint statement released Monday, they endorsed the latest push by the United States, Qatar and Egypt to broker an agreement to end the 10-month-old Israel-Hamas war.

Five Iran-backed fighters have been killed in a drone strike in Syria's east, near the Iraqi border, a war monitor said, adding it was not clear yet who was behind the attack.

"Five pro-Iranian fighters were killed and others were injured, some severely... after an unknown drone targeted the military vehicle they were in... near the Syrian-Iraqi border," said the Syrian Observatory for Human Rights.

Iraq's top Shiite Muslim cleric Grand Ayatollah Ali Sistani has warned of the risk of a regional escalation with potentially "catastrophic consequences" following the killing of two Iran-backed militant leaders.

Sistani also urged an end to the "genocidal war" in Gaza, where the civil defense agency said an Israeli air strike Saturday on a school housing displaced Palestinians killed more than 90 people.

The Israeli military ordered more evacuations in southern Gaza early Sunday after a deadly airstrike on a school-turned-shelter in the north killed at least 80 Palestinians, according to local health authorities. Israel said it targeted a militant command post, killing 19 fighters.

Israel has repeatedly ordered mass evacuations as its troops have returned to heavily destroyed areas where they had previously battled Palestinian militants. The vast majority of Gaza's population of 2.3 million people have been displaced by the 10-month old war, often multiple times.

Haifa's residents gaze warily on to the sprawling industrial port that flanks their Israeli city, knowing the potential for a major blast as they brace for possible bombardment from Hezbollah.

The historic city cascades down a steep hillside to the very edge of the port, a complex which contains Israel's biggest oil refinery, giant fuel tanks and other highly flammable targets.

Gaza's civil defense agency said Saturday an Israeli air strike on a school housing displaced Palestinians killed 93 people, as Israel's military accused militants of using the building as a command center.

AFP could not independently verify the toll which, if confirmed, would appear to be one of the largest from a single strike during 10 months of war between Israel and Hamas Palestinian militants.