Israel will soon halt or slow humanitarian aid into parts of northern Gaza as it expands its military offensive against Hamas, an official said Saturday, a day after Gaza City was declared a combat zone.

The decision was likely to bring more condemnation of Israel's government as frustration grows in the country and abroad over dire conditions for both Palestinians and remaining hostages in Gaza after nearly 23 months of war.

The official, who spoke on condition of anonymity because they were not authorized to speak to the media, told The Associated Press that Israel will stop airdrops over Gaza City in the coming days and reduce the number of aid trucks arriving as it prepares to evacuate hundreds of thousands of people south.