Qatar, a key negotiator of the ceasefire, accused Israel of violating the deal. The U.N. relief chief said aid access must be allowed under international law.

Israel will stop the entry of all humanitarian aid into Gaza to pressure Palestinian militant group Hamas into accepting a temporary extension of the ceasefire agreement, officials said on Sunday, a day after the initial phase of the truce expired.

Food, medicine and shelter stockpiles in Gaza are limited and aid intended for Palestinians in desperate need may spoil following Israel's suspension of deliveries to the enclave, humanitarian agencies said on Monday.