Israel and Hamas brushed off international calls to renew an expired truce Saturday as air strikes pounded militant targets in Gaza and Palestinian groups launched volleys of rockets.

Smoke again clouded the sky over the north of the Palestinian territory, whose Hamas government said 240 people had been killed since a pause in hostilities expired early Friday and combat resumed.

In Israel, the military's Home Front Command reported 40 missile alerts in the south and centre of the country, and the Palestinian groups Hamas and Islamic Jihad announced "rocket barrages" against multiple Israeli cities and towns including Tel Aviv.

"Over 250 rockets have been fired at Israel since Friday morning," Israeli military spokesman Lieutenant Colonel Peter Lerner told reporters. "The vast majority of those have not been successful in reaching their destination. Each one of those, obviously, is intended to kill Israelis."

According to the United Nations, an estimated 1.7 million people in Gaza — more than two-thirds of the population — have been displaced by eight weeks of war.

Fadel Naim, chief doctor at the Al-Ahli Arab hospital in Gaza City, said his morgue had received 30 bodies on Saturday, including seven children.

"The planes bombed our houses: three bombs, three houses destroyed," Nemr al-Bel, 43, told AFP, adding he had counted 10 dead in his family and "13 more still under the rubble".

The population is short of food, water and other essentials, and many homes have been destroyed. UN agencies have declared a humanitarian catastrophe, although some aid trucks did arrive Saturday.

"Homes, hospitals and other infrastructure critical to the survival of the civilian population have suffered colossal destruction," said Pascal Hundt, head of operations in Gaza for the International Committee of the Red Cross (ICRC). 

"Current conditions do not allow for a meaningful humanitarian response, and I fear will spell disaster for the civilian population," he added.

After the truce between Israel and Hamas expired on Friday, Israel had told NGOs not to bring aid convoys across the Rafah border crossing from Egypt, the Palestine Red Crescent Society had said.

But on Saturday, the charity said its Egyptian colleagues had managed to send over a number of trucks.

Israel withdraws negotiators

Both sides blamed each other for the breakdown of the truce, which before it expired had enabled the release of 80 Israeli hostages in exchange for 240 Palestinian prisoners.

The deal had been brokered with the help of Qatar, backed by Egypt and the United States, but on Saturday Israel said it was withdrawing its negotiators from Doha after reaching a dead end in talks aimed at securing a renewed pause in hostilities.

French President Emmanuel Macron appealed for "stepped-up efforts to reach a lasting ceasefire" to free all hostages, allow in more aid and to assure Israel of its security.

During an unprecedented attack on October 7, Hamas fighters broke through Gaza's militarised border into Israel, killed about 1,200 people, mostly civilians, and took around 240 Israelis and foreigners hostage, according to Israeli authorities.

Israel vowed to eliminate Hamas in response and unleashed an air and ground campaign that has killed more than 15,000 people, also mostly civilians, the Hamas authorities who run Gaza say.

Since the end of the pause, Israel's air, naval and ground forces have attacked more than 400 targets in Gaza, the army said on Saturday. 

The figure is roughly in line with the daily average number of strikes prior to the pause, according to military figures released previously.

Warplanes hit "more than 50 targets in an extensive attack in the Khan Yunis area" of Gaza's south, according to the military.

Separately, members of an Israeli armoured brigade "eliminated terrorist squads and directed fire against terrorist targets in the north of the Gaza Strip", the military said.

Fighting spreads

International leaders and humanitarian groups condemned the return to fighting.

"I deeply regret that military operations have started again in Gaza," UN Secretary-General Antonio Guterres said on X, formerly Twitter.

The Lebanese militant group Hezbollah, which like Hamas is backed by Iran, said two of its members were killed Friday in Israeli strikes on Lebanon, as its fighters resumed attacks against Israeli targets following the end of the truce.

Israel's military said its artillery struck the sources of "launches" from Lebanon.

Syria said Israel carried out air strikes near Damascus on Saturday. A British-based war monitor said the strikes on "Hezbollah sites" killed two Syrian pro-Hezbollah fighters.

Iran's Revolutionary Guard accused Israel of killing two of its members in Syria who it said had been on an "advisory mission".

Hamas in October last year said it had restored relations with Syria's government. Israeli attacks on targets in Syria have intensified since the Israel-Hamas war began.

The week of hostage-prisoner exchanges yielded tearful reunions of Israeli families with their released relatives and jubilation in the streets of the Israeli-occupied West Bank as Palestinians walked free from Israeli jails.

Twenty-five other hostages, mostly Thais, were also freed in separate arrangements.

The Israeli army on Friday said 136 hostages were still being held in Gaza, including more than a dozen women.

The end of the pause meant bitter disappointment for the families of those still not freed.

"We saw a chance for people to come out, be reunited with their families and resume their old lives," said Ilan Zharia, the uncle of Eden Yerushalmi, 20, one of the women still held captive.

Romania said it had been told by Israel that a Romanian-Israeli hostage had died in Gaza.