Israel has said it is delaying the release of over 600 Palestinian detainees it had planned to free the day before until Hamas met its conditions, underscoring the fragility of the Gaza ceasefire accord, Reuters reports.

Prime Minister Benjamin Netanyahu’s office released a statement earlier today saying that Israel was waiting to deliver the 620 Palestinian captives and detainees “until the release of the next hostages has been assured, and without the humiliating ceremonies”.

That was a reference to recent handovers by Hamas that UN officials have said went against international law because they were not respectful. Hamas has made hostages appear on stage in front of crowds and sometimes speak before they were handed over. Coffins with hostage remains have also been carried through crowds.

Israel’s announcement comes despite Hamas handing over six hostages from Gaza as part of an exchange arranged under the truce. The bodies of four dead Israeli hostages were to be released next week. It was not clear if Israel wanted assurances on that release or other hostage releases.

After the six hostages arrived back in Israel, Hamas released a video in which two other hostages, Eviatar David and Guy Gilboa-Dalal, were seen watching one of the handovers yesterday.