Nearly 48,000 Palestinians have fled southward in the last two days from the Israeli military's ground offensive in Gaza City, UN humanitarians said on Tuesday.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) said that between mid-August and Monday, its partners observed more than 190,000 such movements, with many people traveling on foot due to the extremely high cost of transport.

"Partners report that displaced families, often led by women and older people, are walking up to nine hours in extreme heat, frequently barefoot and with injured children," OCHA said. "Many are arriving without shelter, and requests from the most vulnerable for family tents are rising."

OCHA said its partners, providing support to those on the move, reported that more than 1,500 people, including more than 900 children, received urgent assistance, including psychosocial aid, water and medical care.

The office said its health-related partners reported that hospitals and clinics remain under immense strain. This week, Al-Quds Hospital in Gaza City sustained damage from nearby bombardments and is now sheltering displaced families. Only three of the six UN medical points in Gaza City run by the UN relief agency remain functional.

OCHA added that the Zikim border crossing has been closed for four days. Fuel and medical missions have been called off due to insecurity, congestion and looting. Aid convoys continue to face delays and risks on the road, preventing assistance from reaching civilians who need it most.

"Despite these immense challenges and dwindling supplies, the UN and its humanitarian partners continue to deliver life-saving assistance and critical services wherever and whenever possible across the Gaza Strip," OCHA said.