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.

Hamas accused Israel of trying to derail the ceasefire agreement hours after its first phase ended. It called the decision to cut off aid “cheap extortion, a war crime and a blatant attack” on the truce,

Israel blocked aid trucks into Gaza as a cease-fire standoff has escalated, with Hamas calling on other mediators to intervene.