Israeli forces battled Hamas militants and bombed more targets in the devastated Gaza Strip on Tuesday with the UN General Assembly due to vote on a new demand for a ceasefire.

More than two months into the war sparked by Hamas's October 7 attack, the visiting chief of the UN agency for Palestinian refugees, Philippe Lazzarini, likened Gaza to "hell on earth".

The Hamas-run health ministry updated its death toll in Gaza to 18,412, mostly women and children.

The militant Islamist group said Israeli forces raided a hospital in Gaza City, the biggest urban centre.

"Israeli occupation forces are storming Kamal Adwan hospital after besieging and bombing it for days," health ministry spokesperson Ashraf al-Qudra said, accusing troops of rounding up men in the hospital courtyard, including medical staff.

The army did not immediately comment, but Israel has repeatedly accused Hamas of using hospitals, schools, mosques and tunnels beneath them as military bases -- claims it has denied.

The UN humanitarian agency OCHA said earlier that "the hospital remains surrounded by Israeli troops and tanks, and fighting with armed groups has been reported in its vicinity for three consecutive days".

It said two mothers were killed in a strike on the maternity ward, and that about 3,000 internally displaced people were trapped in the facility amid reports of "extreme shortages of water, food and power".

The war began with Hamas's October 7 attacks that killed 1,200 people, according to Israeli figures, and saw around 240 hostages taken back to Gaza.

Israel has responded to the unprecedented attack with an offensive aiming to destroy Hamas that has reduced much of Gaza to rubble.

UN agencies and aid groups fear the Palestinian territory will soon be overwhelmed by starvation and disease, and are pleading with Israel to boost efforts to protect civilians.

Air and artillery strikes again rained down on multiple targets in Gaza, a day after Israeli Defence Minister Yoav Gallant reported significant progress in the war, now in its third month.

"Hamas is on the verge of dissolution -- the IDF (Israel Defense Forces) is taking over its last strongholds," he said.

The war has deepened the suffering in Gaza, whose devastation top European Union diplomat Josep Borrell has compared to that of Germany during World War II.

The UN estimates 1.9 million of Gaza's 2.4 million people have been displaced by the conflict, half of them children.

Israeli air strikes killed at least 24 people in Rafah near the border with Egypt, where tens of thousands are seeking shelter, the Gaza health ministry said. (AFP)