The Israeli military on Thursday said it controls 40 percent of Gaza City, the largest urban centre in the Palestinian territory which it is preparing to conquer after nearly two years of devastating war.

Israel has intensified in recent days its bombardments of the area of Gaza City, in the territory's north, ahead of the planned offensive, despite mounting international pressure to halt the campaign.

Gaza's civil defence agency said Israeli strikes on Thursday killed more than 30 people in the city, out of at least 64 Palestinians killed across the Gaza Strip.

As concern grows over the dire humanitarian conditions for Gaza's population of more than two million, one of the European Union's top officials called the war a "genocide" – a term strongly rejected by Israel, but which several governments and numerous rights groups have adopted.

In a televised briefing, Israeli military spokesman Brigadier General Effie Defrin said that "we hold 40 percent of the territory of Gaza City", adding that the offensive "will continue to expand and intensify in the coming days".

Defrin vowed to "increase the pressure" on Palestinian militant group Hamas, whose October 2023 attack on Israel sparked the war, "until it is defeated".

With the vast majority of Gazans already displaced at least once during the war, a senior Israeli military official told journalists on Wednesday that authorities expected the new offensive to push an estimated one million Palestinians south, away from Gaza City.

The United Nations last month declared a famine in and around Gaza City, where it estimates nearly one million people live.

Civil defence spokesman Mahmud Bassal said that an Israeli air strike on Thursday hit a tent sheltering a displaced Palestinian family in Gaza City, killing five people including three children.

Contacted by AFP, the Israeli military said forces had targeted "a Hamas terrorist", adding that it "regrets any harm caused to uninvolved civilians".

In Tel al-Hawa, the neighbourhood where the strike reported by the civil defence took place, AFP footage showed Palestinians outside damaged tents, clearing up scattered belongings.

A pair of blood-stained pink slippers lay amongst the debris.

At Gaza City's Al-Shifa Hospital, where the dead and wounded were being received, bodies wrapped in white shrouds lay on the floor of the hospital's morgue.

One woman stroked the head of her dead son as his body lay outside on a stretcher.

"Who are you leaving me to, son? Why? Why?" she wept.

UNICEF spokeswoman Tess Ingram, briefing journalists from a visit to the Gaza Strip, said that "the unthinkable in Gaza City has already begun", with escalating military operation leading to "the collapse of essential services".

"Without immediate and increased access to food... more children will starve," she said.

"Palestinian life is being dismantled here, steadily but surely." (AFP)