JERUSALEM/UNITED NATIONS/CAIRO - Israel's military spokesperson Effie Defrin said Thursday that Israeli forces control about 40 percent of Gaza City and will "expand and intensify" the offensive in the coming days to seize the enclave's largest urban center.

Defrin said in a briefing that as part of the assault, which he said began "in recent weeks," tens of thousands of reservists have been mobilized to join regular forces currently maneuvering in the Zeitoun neighborhood in the southeast of the city and in Sheikh Radwan in the north.

"Hamas will meet the full force of the IDF (Israel Defense Forces) in Gaza City," Defrin said. "We will increase the pressure on Hamas until its defeat."

Defrin showed aerial video footage of several blocks exploding, which he said was the destruction of underground infrastructure in Zeitoun.

His remarks came a day after Israeli Prime Minister Benjamin Netanyahu rejected Hamas' offer to pursue a "comprehensive deal" to end the war and secure the release of hostages, describing it as "spin."

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Israel's new assault on Gaza City, already devastated by nearly two years of intensive attacks, drew condemnation over its impact on civilians. Israeli strikes have destroyed much of the city's infrastructure, large parts of the population have been displaced multiple times, and aid groups say famine is taking hold.

Since Oct 7, 2023, Israel's military campaign in Gaza has killed 64,232 people and injured 161,583 others, Gaza-based health authorities said Thursday, adding that starvation and malnutrition in Gaza have caused 370 deaths, including 131 children.

'City of fear, flight and funerals'

Also on Thursday, Tess Ingram, UNICEF Communication Manager for the Middle East and North Africa Regional Office, said Gaza City, the last refuge for families in the northern Gaza Strip, is fast becoming a place where childhood cannot survive.

"It is a city of fear, flight and funerals," Ingram told a daily briefing at the UN headquarters in New York, via video conferencing from the Gaza Strip.

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The world is sounding the alarm about what an intensified military offensive in Gaza City could bring -- a catastrophe for the almost 1 million people who remain there, she said.

"It would be an unthinkable tragedy, and we must do everything in our power to prevent it," said Ingram.

Ingram said that over nine days, she met families in Gaza City who fled their homes in fear - already displaced, now displaced again - arriving with nothing but the clothes on their backs.

"I met children who were separated from their parents in that chaos. Mothers whose children have died of starvation. Mothers who fear their children will be next. I've spoken to kids in hospital beds, their small bodies shredded by shrapnel," she said.

According to Ingram, only 44 of the 92 UNICEF-supported outpatient nutrition treatment centers in Gaza City are still functioning, depleting thousands of malnourished children of more than half of the lifelines they depend on to fight famine.

"Our team is doing everything in their power to help children. But we could do far more, reach every child here, if our operations on the ground were enabled at scale and we were well funded," she said.

Israel's measures to isolate Jerusalem rejected

Meanwhile, an Arab ministerial committee rejected "the Israeli measures to isolate Jerusalem", stressing that "Israel has no sovereignty over Jerusalem and its Islamic and Christian holy sites."

The committee, in charge of international action to confront illegal Israeli policies and measures in Jerusalem, issued a joint statement following its 10th meeting on the sidelines of the 164th regular meeting of the Council of the Arab League (AL).

The committee, formed by the AL in 2021 and chaired by Jordan, includes Iraq, Palestine, Algeria, Somalia, Saudi Arabia, Qatar, Egypt, Morocco, Tunisia, and the AL secretary-general.

In the statement, the committee condemned Israel's recent approval of the E1 settlement plan as a prelude to "besieging the Old City and isolating it from its Palestinian surroundings".

The approval is an attempt to "undermine the establishment of a Palestinian state and a blatant assault on the right of the Palestinian people to embody their independent state", it said.

It condemned all measures aimed at changing the demographic composition and the historical and religious character of Jerusalem, noting that these measures are in opposition to international laws and legitimate international resolutions.

It also slammed Israel's attempts to "impose facts and practices aimed at the temporal and spatial division" of the Al-Aqsa Mosque compound, and to limit the free access of Muslim worshippers to the compound.

Israel occupied East Jerusalem and the West Bank in the Six-Day War of 1967 and has since built settlements widely deemed illegal under international law. It has accelerated settlement activities in recent years.

In late August, it approved the construction of 3,401 housing units in E1, located east of Jerusalem, linking the large-scale settlement of Maale Adumim with East Jerusalem.