Israel said Sunday it has stopped the entry of all humanitarian aid into Gaza after phase one of its ceasefire deal with Hamas expired, citing the militant group’s refusal of a US-backed extension.

The first phase of the Israel-Hamas ceasefire, which included a surge in humanitarian assistance, expired on Saturday. The two sides have yet to negotiate the second phase, in which Hamas was to release dozens of remaining hostages in return for an Israeli pullout and a lasting ceasefire.