Israel faced growing US calls to avoid further harm to Palestinian civilians in its fight against Hamas militants in Gaza, as the warring sides on Sunday showed no sign of moving toward reviving their collapsed truce.

As Israeli forces pounded the enclave following the breakdown of a temporary ceasefire, US Vice President Kamala Harris said too many innocent Palestinians had been killed in Gaza, and US Defence Secretary Lloyd Austin deemed it a “moral responsibility” for Israel to protect civilians.

The senior US officials' remarks on Saturday reinforced pressure from Washington for Israel to use more caution as it shifts the focus of its military offensive further south in the besieged Gaza Strip.

With renewed fighting stretching into a third day, residents feared the air and artillery bombardment was just the prelude to an Israeli ground operation in the southern strip that would pen them into a shrinking area and possibly try to push them across into Egypt.

The Gaza health ministry said at least 193 Palestinians had been killed since the weeklong truce ended on Friday, adding to the more than 15,000 Palestinian dead since the start of the war. Israel has sworn to annihilate Hamas following its Oct. 7 rampage in southern Israel in which it says 1,200 people were killed and more than 200 taken hostage.

Speaking in Dubai, Harris said Israel had a right to defend itself, but international and humanitarian law must be respected and “too many innocent Palestinians have been killed.”

“Frankly, the scale of civilian suffering, and the images and videos coming from Gaza, are devastating,” Harris told reporters.

Austin weighed in with perhaps his strongest comments to date on Israel's need to protect civilians in Gaza, calling it “moral responsibility and strategic imperative.”

“If you drive them into the arms of the enemy, you replace a tactical victory with a strategic defeat,” Austin told a defense forum in Simi Valley, California.

Austin, who pledged that the US would stand by Israel as its “closest friend in the world,” also said he pressed Israeli officials to dramatically expand Gaza's access to humanitarian aid.

Prime Minister Benjamin Netanyahu, at a news conference in Tel Aviv on Saturday, said Israel was continuing to work in coordination with the US and international organizations to define “safe areas” for Gaza civilians.

“This is important because we have no desire to harm the population,” Netanyahu said. “We have a very strong desire to hurt Hamas.”

The United States has been increasingly vocal that Israel must narrow the combat zone during any offensive in southern Gaza and ensure safe zones for non-combatants.

Israel has vowed to wipe out Hamas once and for all. The Iranian-backed Islamist group is sworn to Israel’s destruction. One of its officials has said Hamas would repeat the Oct. 7 attacks if possible.

The Israeli military said it had killed Wessam Farhat, commander of a Hamas battalion who sent fighters to hit two kibbutzim near the Gaza Strip on Oct. 7. It also described him as one of the planners of the raid.

'New layer of destruction'

Mark Regev, a senior adviser to Netanyahu, said Israel did not want to see Gaza's civilians caught in the crossfire and was making a “maximum effort” to safeguard them.

He said that when the war was over, Israel would seek a “security envelope” to prevent Hamas from positioning itself on the Gaza border.

Robert Mardini, head of the International Committee of the Red Cross, told Reuters the renewed fighting was “a new layer of destruction coming on top of massive, unparalleled destruction.”

Gaza health officials said that in addition to the death toll, 650 people had been wounded since the truce collapsed.

With conditions inside Gaza reaching the “breaking point,” in Mardini's words, the first aid trucks since the end of the truce entered from Egypt through the Rafah crossing on Saturday, Egyptian security and Red Crescent sources said. Some 100 trucks passed through, the sources said.

A senior official said Israel would facilitate the provision of humanitarian aid to Gaza's civilians.

The warring sides blamed each other for the collapse of the truce, during which Hamas had released hostages in exchange for Palestinian prisoners held in Israeli jails.

Israel said it had recalled a team from Qatar, host of indirect negotiations with Hamas, accusing the Palestinian faction of reneging on a deal to free all the women and children it was holding.

French President Emmanuel Macron, meanwhile, said he was heading to Qatar to work on a new truce.

The deputy head of Hamas, however, said no prisoners would be exchanged with Israel unless there is a ceasefire and all Palestinian detainees in Israel are released.

Saleh Al-Arouri told Al Jazeera TV that Israeli hostages held by Hamas are soldiers and civilian men who previously served in the army.

But Israeli Defense Minister Yoav Gallant said Hamas breached its commitment to free 17 women and children still held in Gaza.

South targeted

The southern part of Gaza, including Khan Younis and Rafah, where hundreds of thousands of people displaced from the north of the enclave had sought refuge, was pounded on Saturday.

The Palestinian News Agency quoted local sources as saying warplanes bombed two homes in the Nuseirat refugee camp, killing at least 13 people. Gaza health officials said three Palestinians were killed in an Israeli air strike on a house in Rafah.

Reuters could not independently verify the accounts.

Hamas said it targeted Tel Aviv with a rocket barrage. There were no reports of damage, but paramedics said one man was treated for a shrapnel injury in central Israel.