Israel on Sunday said it was delaying the release of hundreds of Palestinian prisoners it had planned to free the day before until militant group Hamas met its conditions.

This underscored the fragility of the Gaza ceasefire accord.

This was contained in a statement by the office of Prime Minister, Benjamin Netanyahu in the early hours of Sunday.

According to the statement, Israel was waiting to deliver the 620 Palestinian prisoners and detainees until the release of the next hostages has been assured, and without the humiliating ceremonies.

The announcement, which also accused Hamas of repeatedly violating the month-old ceasefire, came after the Palestinian militant group on Saturday handed over six hostages from Gaza as part of an exchange arranged under the truce.

The six hostages released on Saturday were said to be the last living Israeli captives due to be handed over during the first phase of the ceasefire.

Meanwhile, the bodies of four dead Israeli hostages were to be released next week.

After the six hostages arrived back in Israel, it was gathered that Hamas released a video in which two other hostages, Eviatar David and Guy Gilboa-Dalal, were seen watching one of the handovers earlier on Saturday.

Hamas spokesperson, Abdul Latif Al-Qanou earlier accused Israel of violating the ceasefire as Saturday elapsed without the release of Palestinians as planned.

Israel and Hamas have frequently accused each other of violations since the ceasefire started on January 19 but it has so far continued to hold.

Hamas at one stage said it would stop handing over hostages because of alleged Israeli breaches.