United Nations, Aug 21 (IANS): The latest Israeli evacuation order for Gaza is constraining the movement of aid operations already hampered by limited access, fuel shortages and other challenges, UN humanitarians have said.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) said on Tuesday the challenges of relentless hostilities and repeated evacuation orders constrained aid operations, Xinhua news agency reported.

OCHA said the latest evacuation order released on Saturday for parts of Deir al Balah included sections of the Salah ad Din Road, a crucial passage for humanitarian missions.

"This has made it nearly impossible for aid workers to move along this key route," the office said. "The Coastal Road is not a viable alternative. The beaches along this route are now crowded with makeshift shelters for displaced Palestinians."

OCHA said that as a result, convoy movements along the Coastal Road were extremely slow, and critical supplies and services -- such as water trucking -- were not reaching people in need at anywhere near the scale required.

Only last Friday, UN Secretary-General Antonio Guterres announced a UN campaign to administer two doses each of a polio vaccine to more than 640,000 children under the age of 10 in Gaza after the virus was detected in wastewater earlier this month. He sought a pause in hostilities for the campaign to begin later this month.

OCHA said on Monday, in its latest Humanitarian Situation Update, that "A 10-month-old baby is the first confirmed case of active poliomyelitis, according to the Palestinian Ministry of Health."