Australia's decision to halt funding to a United Nations organisation aiding Palestinian refugees has been described by advocates as a death sentence for people on the ground in Gaza.
Australia joined the United States, United Kingdom and Canada in freezing funding for the United Nations Relief and Works Agency for Palestinian Refugees (UNRWA) after allegations a dozen staff helped Hamas in its attack on Israel.
Hamas has been designated a terrorist organisation by Australia.
Two million civilians, half of whom are children in Gaza, rely on the UNRWA to survive, ActionAid Australia executive director Michelle Higelin said.
"This reckless action by Australia and other governments spells a death sentence for millions of Palestinians in Gaza and the surrounding region, intensifying an already catastrophic humanitarian crisis for millions of people," she said.
"This heartless decision will strip away life-saving assistance at a time when civilians face the grim reality of starvation, impending famine and the spread of diseases."
The funding freeze would also cut the jobs of local staff who would lose income during a humanitarian emergency, she said.
"UNRWA is a vital lifeline for Palestinians in the Gaza Strip, it is the largest humanitarian organisation in the region and plays an indispensable role in providing vital aid."
More than 20 international aid organisations have called for the reinstatement of UNRWA funding.
"We are shocked by the reckless decision to cut a lifeline for an entire population by some of the very countries that had called for aid in Gaza to be stepped up and for humanitarians to be protected while doing their job," Save the Children said.
More humanitarian aid was desperately needed in Gaza to prevent mass starvation, suffering and trauma, Caritas' Sally Thomas said.
"What is missing in global decision-making is empathy for a population on its knees," Ms Thomas said.
"A catastrophe of trauma, already well underway, will increasingly bear out in the months and years to come, alongside the impact of prolonged malnutrition and a lack of education on the development of Palestinian children."
A failure to provide humanitarian aid as Palestinians starve and are left homeless while injured children are having amputations without anaesthetic further risks regional escalation as other nations react, she said.
Palestine's envoy in Australia Izzat Abdulhadi called the funding freeze "collective punishment", saying that 12 people being investigated in an agency of 30,000 shouldn't mean millions are deprived of aid.