Gaza’s main hospital is “nearly a cemetery” as bodies pile up and doctors fear for hundreds of patients unable to receive life-saving medical treatment as fighting rages outside.

Israeli forces on Tuesday (AEDT) reached the gates of Gaza City’s main hospital, Al Shifa, the primary target in the northern Gaza Strip where medics say patients, including newborn babies, are dying for lack of fuel.

The Israel Defence Force issued an evacuation order, but doctors refused to leave because they feared for 700 patients who would die if they were left behind.

“And if they are transferred they will die on the way, this is the problem,” Doctor Munir Al-Bursh, director-general of the Hamas-run Health Ministry, told CNN.

Premature babies were taken out of incubators after the hospital’s last generator was hit. The infants have reportedly been wrapped in foil and put near hot water to try to keep them warm and alive.

Israel has accused Hamas of running a command centre under the hospital – which Hamas and hospital officials reject – and of commandeering fuel that the Israeli military supplied for the premature babies.

World Health Organisation spokesman Christian Lindmeier said the hospital was filling up with dead bodies “which cannot be taken care of or not even be buried or taken away to any sort of morgue”.

“The hospital is not working at all anymore as well as it should. It’s nearly a cemetery,” he said.

An earlier image of 33 premature babies at Al Shifa Hospital. Photo: Getty

Gaza health ministry spokesperson Ashraf Al-Qidra, who was inside Al Shifa hospital, said 32 patients had died in the past three days, including three newborn babies, as a result of the siege of the hospital and lack of power.

At least 650 patients were still inside, desperate to be evacuated to another medical facility by the Red Cross or some other neutral agency.

Israel says the hospital sits atop tunnels housing a headquarters for Hamas fighters using patients as shields, which Hamas denies.

“The tanks are in front of the hospital. We are under full blockade. It’s a totally civilian area. Only hospital facility, hospital patients, doctors and other civilians staying in the hospital. Someone should stop this,” a surgeon at the hospital, Dr Ahmed El Mokhallalati, said by telephone.

“They bombed the [water] tanks, they bombed the water wells, they bombed the oxygen pump as well. They bombed everything in the hospital. So we are hardly surviving.

“We tell everyone, the hospital is no more a safe place for treating patients. We are harming patients by keeping them here.”

There was also fresh concern that the war could spread beyond Gaza, with an upsurge of clashes on Israel’s northern border with Lebanon, and the US launching air strikes on Iran-linked militia targets in neighbouring Syria.

Israel launched its campaign last month to annihilate Hamas, the militant group which runs the Gaza Strip, after Hamas fighters rampaged through southern Israel killing civilians. About 1200 people died and 240 were dragged to Gaza as hostages according to Israel’s tally, in the deadliest day in its 75-year history.

Gaza authorities say more than 11,000 people have been killed in Israel’s month-long attack.

Since then thousands of Gazans have been killed and two-thirds of the population made homeless by a relentless Israeli military campaign. Gaza medical authorities say more than 11,000 people have been confirmed killed, about 40 per cent of them children.

Since Israeli ground forces entered Gaza in late October and quickly surrounded Gaza City, fighting has been concentrated in a tightening circle around Al Shifa, the enclave’s biggest hospital.

Gaza health ministry spokesperson Qidra said an Israel tank was stationed at the hospital gate. Israeli snipers and drones were firing into the hospital, making it impossible for medics and patients to move around.

“We are besieged and are inside a circle of death,” he said.

Gaza has been flattened, with homes and livelihoods lost. Photo: Getty

Israel has told civilians to leave and medics to send patients elsewhere. It says it has attempted to evacuate babies from the neonatal ward and left 300 litres of fuel to power emergency generators at the hospital entrance, but the offers were blocked by Hamas.

Dr El Mokhallalati, the surgeon, said premature babies that would normally be in individual incubators were being lined up eight to a bed, kept warm with whatever power was left.

After three died there were 36 alive in the neo-natal unit, he said.

“We are expecting to lose more of them day by day.”

Israel released footage of men armed with a grenade launcher at the al-Quds hospital gate.

There was also fighting at a second major hospital in northern Gaza, al-Quds, which has also stopped functioning. The Palestinian Red Crescent said the hospital was surrounded by heavy gunfire, and a convoy sent to evacuate patients and staff had been unable to reach it.

Israel said it had killed “approximately 21 terrorists” at al-Quds in return fire after fighters shot from the hospital entrance. It released footage purporting to show a group of men at the hospital gate, one of whom appeared to be carrying a rocket-propelled grenade launcher.

UN agencies observed a minute’s silence on Monday for 101 staff members killed so far in Gaza, the largest toll of humanitarian workers since the UN was founded in the ashes of World War II.

-with AAP