Aid trucks stalled at the Gaza border, hospitals treating missing limbs: UN Security Council envoys visiting Egypt on Monday encountered the fallout of the Israel-Hamas war, days after the United States vetoed a ceasefire resolution.

The informal one-day trip organised by the United Arab Emirates and Egypt came amid a spiraling humanitarian crisis in war-devastated Gaza.

Around a dozen ambassadors took part from countries including Russia and Britain.

But the US, which vetoed the Security Council resolution calling for a ceasefire on Friday, did not send a representative and neither did France.

"I am not sure what the US would have seen today would have been very pleasing for them," Russia's United Nations ambassador Vassily Nebenzia told AFP at the Rafah crossing, the main gateway into Gaza and the epicentre of the humanitarian response.

"They would have seen what is really happening and not what their geostrategic motives are shielding them" from, he added, calling the situation a "catastrophe".

Earlier, the envoys visited a hospital in El-Arish near the Rafah crossing, treating people who had been evacuated from the conflict.

Ecuador's envoy Jose de la Gasca told AFP he was "destroyed" by the visit to the hospital.

"I just met a young mother who lost a kid and has another little girl who is wounded," he said.

The diplomats later visited the Rafah crossing via a stretch of road lined with aid trucks waiting for permission to enter Gaza.

The entry of aid is also tightly restricted. Only a trickle has entered the coastal Palestinian territory since a week-long truce broke down at the start of the month.

Monday's trip marked a last-ditch diplomatic effort by the UAE to generate support for a ceasefire ahead of the expiry of its two-year term on the council at the end of the month.

There is "deep frustration, disappointment and some outrage... (that) we can't even reach a consensus for a ceasefire," Lazzarini said. (AFP)