The United Nations, United States and Canada appealed on Tuesday for a humanitarian pause in the Israel-Hamas war to allow safe deliveries of aid to civilians stricken by shortages of food, water, medicine and electricity in the Israeli-besieged enclave.

International pressure for unimpeded aid to Gaza rose as the health ministry in the Hamas-ruled territory reported that Israeli air strikes had killed more than 700 Palestinians overnight. Ministry spokesman Ashraf Al-Qidra said this was the highest 24-hour death toll in Israel's two-week-old siege.

UN agencies were pleading "on our knees" for emergency aid to be let into Gaza unimpeded, saying more than 20 times current deliveries were needed to support the narrow strip's 2.3 million people amid widespread devastation from Israel's aerial blitz.

The United States is negotiating with Israel, neighbouring Egypt and the UN to smooth emergency deliveries into Gaza, but have wrangled over procedures for inspecting the aid and bombardments on the Gaza side of the border.

In a statement released on social media, the Palestinian health ministry said at least 5,791 Palestinians had been killed by Israeli bombardments since October 7, including 2,360 children. Some 704 were killed in the previous 24 hours alone, it said.

Reuters could not independently verify the ministry figures.

The Israeli military said that it killed dozens of Hamas fighters overnight while hitting over 400 Hamas targets, but that it would take time to destroy the Islamist militant group whose deadly cross-border attack on October 7 stunned Israel.

UN Secretary-General Antonio Guterres pleaded on Tuesday for civilians to be protected, voicing concern about "clear violations of international humanitarian law" in Gaza.

Doctors in Gaza say patients arriving at hospitals are showing signs of disease caused by overcrowding and poor sanitation after more than 1.4 million people fled their homes for temporary shelters under Israel's heaviest-ever bombardment.

All hospitals say they are running out of fuel to power their electricity generators, leaving them increasingly unable to treat the injured and ill. More than 40 medical centres have halted operations, a health ministry spokesman said.

UNRWA, the UN agency for Palestinian refugees, warned in a post on messaging platform X that it would halt operations in Gaza on Wednesday night because of the lack of fuel. However, the Israeli military reaffirmed it would not permit the entry of fuel to prevent Hamas from seizing it.

The UN said 20 trucks that had been due to deliver aid to Gaza via the Rafah crossing from Egypt on Tuesday could not do so, but it hoped the convoy would get in on Wednesday. (Reuters)