JERUSALEM - Five UN aid trucks entered war-torn Gaza on Monday, a unit under Israel's Defense Ministry said, a day after Israel agreed to lift over two months of blockade and allow limited relief into the enclave -- a step the UN considered far from adequate to meet dire humanitarian needs in Gaza.

The trucks loaded with aid, including baby formula, passed through the Kerem Shalom border crossing after undergoing security inspections, according to the office of the Coordinator of Government Activities in the Territories (COGAT), an official Israeli unit responsible for civilian affairs in the occupied Palestinian territories.

"The IDF (Israel Defense Forces) will continue to facilitate humanitarian assistance in Gaza while making every effort to ensure the aid does not fall into Hamas' hands," COGAT said in a post on social media platform X.

However, UN Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator Tom Fletcher said on X that the trucks were "a drop in the ocean," stressing the aid "must reach the civilians who need it so urgently, and we must be allowed to scale up".

Earlier on Monday, Hamas' media office said that to avert a full-scale humanitarian crisis in Gaza, the entry of 500 aid trucks is required at a daily minimum. In addition, the enclave needs 50 fuel trucks per day to operate bakeries, hospitals, and water and sewage stations, which have shut down due to the Israeli blockade since March 2.

Israeli Prime Minister Benjamin Netanyahu said Sunday that Israel would allow the entry of a "minimal and basic" quantity of aid into Gaza to prevent "images of mass starvation". The decision comes amid a recommendation by the Israeli military, pressure from Israel's close allies, and increasing international criticism over the severe humanitarian crisis in Gaza.

The aid entered as Israel launched its new military campaign, dubbed Gideon's Chariots, over the weekend. Israeli officials said the campaign's objectives include seizing key parts of Gaza, pushing a majority of its population further south, and resuming humanitarian aid distribution under stricter Israeli oversight.

The Israeli military announced on Monday that it had struck 160 locations across Gaza in the past hours, targeting militants, anti-tank missile launchers, military infrastructure, and a weapons depot. It also reported dismantling a tunnel in southern Gaza and hitting a structure in Nuseirat, central Gaza, which it said has served as a Hamas command and control center.

At least 136 people were killed by Israeli strikes over the past day, bringing the overall death toll since the war began on Oct 7, 2023, to 53,475, the Gaza-based health authorities reported on Monday.