Hamas pledged to confront Israeli attacks with "full force" after Israel's military widened its air and ground attacks on the Palestinian enclave, suggesting on Saturday that a long promised ground offensive had begun.

Israel said on Saturday morning its troops, sent in on Friday night, were still in the field, without elaborating. The country had earlier made only brief sorties into Gaza during three weeks of bombardment to root out Hamas militants, who it said had killed 1,400 Israelis on October 7.

"The forces are still in the field and continuing the war," Israel's Rear Admiral Daniel Hagari told a news briefing on Saturday morning.

Gaza was under an almost complete blackout, with internet and phone services cut for more than 12 hours by Saturday morning. Telecoms firms and the Palestinian Red Crescent Society said it was the result of Israeli bombardments.

Hagari said Israel would allow trucks carrying food, water and medicine to enter Gaza on Saturday, indicating that bombing might pause, at least in the area of its border with Egypt where small amounts of aid have been arriving.

Aid agencies have said a humanitarian catastrophe is unfolding in Gaza, whose 2.3 million people are under a total Israeli blockade. Health authorities in Hamas-run Gaza Strip said on Friday that 7,326 Palestinians had been killed since Israel's bombardment began.

The head of the World Health Organization (WHO), Tedros Adhanom Ghebreyesus, said the blackout was "making it impossible" for ambulances to reach the injured in Gaza.

"Evacuation of patients is not possible under such circumstances, nor to find safe shelter," he said in a post on X, formerly known as Twitter. He also said the WHO was not able to contact its staff and health facilities.

The UN General Assembly on Friday adopted a resolution that calls for a humanitarian truce in Gaza.

The resolution calls for "an immediate, durable and sustained humanitarian truce leading to a cessation of hostilities," including protection of civilians and civilian subjects, protection of humanitarian personnel and facilities, and "immediate and unconditional release" of all civilians being illegally held captive.

The resolution was adopted with 120 votes in favor, 14 votes against, and 45 abstentions.

Countries that voted against the draft resolution include Austria, Croatia, the Czech Republic, Fiji, Guatemala, Hungary, Israel, the Marshall Islands, Micronesia, Nauru, Papua New Guinea, Paraguay, Tonga and the United States.

An amendment led by Canada did not pass, as it failed to reach the required two-thirds majority. The amendment would have condemned the October 7 attack on Israel and the taking of hostages by Hamas and would have called for the release of hostages.

Israeli Foreign Minister Eli Cohen rejected the resolution. "We reject outright the UN General Assembly despicable call for a ceasefire," Cohen wrote on X, adding that Israel intends to eliminate Hamas.

(With input from agencies)