Israel has pressed its offensive against Hamas in Gaza after the United States blocked an extraordinary UN bid to call for a ceasefire in the two-month escalation, AFP reports.

An Israeli strike on the southern city of Khan Yunis killed six people, while five others died in a separate attack in Rafah, the ministry said.

Vast areas of Gaza have been reduced to rubble and the UN says about 80 per cent of the population has been displaced, with dire shortages of food, fuel, water and medicine reported.

“It’s so cold, and the tent is so small. All I have are the clothes I wear, I still don’t know what the next step will be,” said Mahmud Abu Rayan, displaced from Beit Lahia in the north.