Several Arab states and the UN have condemned Israel for blocking the entry of all humanitarian aid into the Gaza Strip.
According to foreign media, Egypt and Qatar said the Israeli move on Sunday violated the ceasefire agreement, while UN humanitarian chief Tom Fletcher described it as "alarming."
Israeli Prime Minister Benjamin Netanyahu said his country acted because Hamas was stealing supplies and using them "to fund its terrorist machine."
He also accused the Palestinian group of rejecting a US proposal to extend the ceasefire in Gaza after it expired on Saturday. Israel said it had approved the proposal.
A Hamas spokesman said Israel's blockade was "blackmail" and a "coup" against the ceasefire agreement.
The ceasefire agreement halted 15 months of fighting between Hamas and the Israeli military, allowing the release of 33 Israeli hostages for about 1,900 Palestinian prisoners and detainees.
In a statement on Sunday, Qatar's foreign ministry said it "strongly condemns" the Israeli decision, describing it as "a clear violation of the ceasefire agreement" and "international humanitarian law."
In Egypt, the foreign ministry accused Israel of using starvation as "a weapon against the Palestinian people," the AFP news agency reported.
Both Qatar and Egypt helped broker the Gaza ceasefire agreement.
Meanwhile, Saudi Arabia expressed its "condemnation and denunciation" of the Israeli aid blockade, the Foreign Ministry said.
Tom Fletcher, the UN Under-Secretary-General for Humanitarian Affairs, wrote in a post on X: "International humanitarian law is clear: We must be allowed access to deliver vital life-saving assistance."
Netanyahu said Israel had decided to act "because Hamas steals supplies and prevents the people of Gaza from receiving them."
"She uses these supplies to fund her terrorist machine, which directly targets Israel and our civilians, and we cannot accept that."
Hamas has previously denied stealing humanitarian aid in Gaza. (A2 Televizion)