The plan to expand military operations, approved by Israel's security cabinet overnight, includes holding territories in the besieged Gaza Strip and moving the population south "for their protection", an Israeli official said.
But Gaza residents said that they did not expect the new offensive would make any significant changes to the already dire humanitarian situation in the small coastal territory.
"Israel has not stopped the war, the killing, the bombing, the destruction, the siege, and the starvation -- every day -- so how can they talk about expanding military operations?" Awni Awad, 39, told AFP.
Awad, who lives in a tent in the southern Gaza city of Khan Younis after being displaced by Israeli evacuation orders, said that his situation was already "catastrophic and tragic".
"I call on the world to witness the famine that grows and spreads every day," he said.
The UN's World Food Programme (WFP) in late April said it had depleted all its foods stocks in Gaza due to Israel's blockade on all supplies since March 2.
Aya al-Skafy, a resident of Gaza City, told AFP her baby died because of malnutrition and medicine shortages last week.
Umm Hashem al-Saqqa, another Gaza City resident, fears her five-year-old son might face a similar fate, but is powerless to do anything about it.
"There is no food, no medicine, and no nutritional supplements. The markets are empty of food, and the government clinics and pharmacies have nothing."
Gaza City resident Mohammed al-Shawa, 65, said that Israel's new military roadmap changes little as it already controls most of Gaza.
The UN's Office for the Coordination of Humanitarian Affairs (OCHA) estimates that 69% of Gaza has now been either incorporated into one of Israel's buffer zones, or is subject to evacuation orders.
That number rises to 100% in the southern governorate of Rafah, where over 230,000 people lived before the war but which has now been entirely declared a no-go zone.
"There is no food, no medicine, and the announcement of an aid distribution plan is just to distract the world and mislead global public opinion," Shawa said, referring to reports of a new Israeli plan for humanitarian aid delivery that has yet to be implemented.
Israeli Finance Minister Bezalel Smotrich praised the new plan for Gaza Monday and evoked a proposal previously floated by US President Donald Trump to displace the territory's residents elsewhere.