Hungry Palestinian children scramble to get a container of food. (AP)

JERUSALEM, Israel (AP) — An independent group of experts warned Tuesday that it's possible that famine is underway in northern Gaza but that the war between Israel and Hamas and restrictions on humanitarian access have impeded the data collection to prove it.

"It is possible, if not likely,” the group known as the Famine Early Warning Systems Network, or FEWS NET, said about famine in Gaza.

Concerns about deadly hunger have been high in recent months and spiked after the head of the World Food Program last month said northern Gaza had entered “full-blown famine” after nearly seven months of war. Experts at the U.N. agency later said Cindy McCain was expressing a personal opinion.

An area is considered to be in famine when three things occur: 20% of households have an extreme lack of food, or are essentially starving; at least 30% of the children suffer from acute malnutrition or wasting, meaning they’re too thin for their height; and two adults or four children per every 10,000 people are dying daily of hunger and its complications.

That's according to the Integrated Food Security Phase Classification, a collection of U.N. agencies, governments and other bodies that in March warned famine was imminent in northern Gaza.

Tuesday’s report by FEWS NET is the first technical assessment by an international organization saying that famine is possibly occurring in northern Gaza.

Funded by the United States Agency for International Development, FEWS NET is an internationally recognized authority on famine that provides evidence-based and timely early warning information for food insecurity. It also helps inform decisions on humanitarian responses in some of the world’s most food insecure countries.

But for a formal declaration of famine, the data must be there.

Such a declaration could be used as evidence at the International Criminal Court as well as at the International Court of Justice, where Israel faces allegations of genocide.

The report cautioned that data collection would likely be impeded as long as the war goes on. It said people — including children — are dying of hunger-related causes across the territory and that those conditions will likely persist until at least July, if there isn’t a fundamental change in how food aid is distributed.

The report also cautioned that efforts to increase aid into Gaza are insufficient, and urged Israel's government to act urgently.

The U.N. and international aid agencies for months have said not enough food or other humanitarian supplies are entering Gaza, and Israel faces mounting pressure from top ally the U.S. and others to let in more aid.

Israel has repeatedly denied there is famine underway in Gaza and rejected allegations it has used hunger as a weapon in its war against the militant Hamas group. It has opened a number of new crossings into Gaza in recent months, saying they helped increase the flow of aid.

But Israel has also been expanding its offensive in Gaza's southern city of Rafah, once the main hub of humanitarian aid operations. That invasion has largely cut off the flow of food, medicine and other supplies to Palestinians facing hunger.

The Israeli military, which is responsible for the crossings into Gaza, did not immediately respond to a request for comment on the FEWS NET report.