UNITED NATIONS, Aug. 8 (Xinhua) -- Gazan civilians enduring a heat wave say most basic daily tasks like finding food and water have become impossible, UN humanitarians reported Friday.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) said Gazans are facing mounting challenges amid ongoing hostilities, displacement and further destruction.

"Aid entering into Gaza remains far below the minimum required to meet people's immense needs," OCHA said. "The United Nations and its humanitarian partners continue to do everything possible to bring assistance inside Gaza."

Aid missions continue to face significant delays. OCHA said that a mission on Thursday took 18 hours to complete.

Daytime temperatures in the Gaza Strip reached the low 30s Celsius on Thursday and Friday, with similar weather forecasts for the coming days.

In the southern part of the Gaza Strip, humanitarian partners working on water, sanitation and hygiene reported that the South Gaza seawater desalination plant's electricity line was damaged on Thursday, the third time over the past seven days. As a result, the plant was operating at less than 14 percent of its capacity, said the office.

Since the entry of some commercial trucks into Gaza over the past few days, OCHA has reported that its partners have noted a minor reduction in commodity prices, although most food items remain scarce in the market and are sold at exorbitant prices.

The office said that airdrops landing in different parts of Gaza continue to reportedly kill and injure people, reiterating that the most efficient way to bring in supplies is by road.

Aid must be "allowed to enter through all crossings and via all available corridors so that the UN and its partners can deliver it at scale in a safe and dignified manner through their community-based mechanisms, reaching the most vulnerable," the office said.

Also, a statement issued by Stephanie Tremblay, associate spokesperson for UN Secretary-General Antonio Guterres, on Friday said that the secretary-general is gravely alarmed by the Israeli decision to "take control of Gaza City."

"This decision marks a dangerous escalation and risks deepening the already catastrophic consequences for millions of Palestinians, and could further endanger more lives, including (those) of the remaining hostages," the statement said.

"The secretary-general warns that this further escalation will result in additional forced displacement, killings and massive destruction, compounding the unimaginable suffering of the Palestinian population in Gaza," it added.