Hamas has said it is delaying the release of a second group of hostages, claiming that Israel had not complied with the deal’s terms and not delivered enough aid to the besieged enclave.

Hamas did not specify the delay’s length.

The last-minute snag created a tense standoff on the second day of what was meant to be a four-day ceasefire.

As night fell and as the hostages should have emerged from Gaza, Hamas announced that it was delaying the release over what it said were Israeli truce violations.

The group alleged the aid deliveries permitted by Israel fell short of what was promised, and that not enough of the aid was reaching northern Gaza — the focus of Israel’s ground offensive and the main combat zone.

Hamas also said not enough veteran prisoners were freed in the first swap on Friday.

“This is putting the deal in danger and we have spoken to mediators about that,” Osama Hamdan, a senior Hamas official, said in Beirut.

The UN agency for Palestinian refugees said 196 trucks of aid entered on Friday, and Israel said four fuel trucks and four tanks of gas entered Saturday.

Hamas was preparing to release more than a dozen hostages on Saturday for several dozen Palestinian prisoners held by Israel, on the second day of a ceasefire that has allowed critical humanitarian aid into the Gaza Strip and given civilians their first respite after seven weeks of war.

While uncertainty around the details of the exchange remained, there was optimism, too, amid scenes of joyous families reuniting on both sides. On the first day of the four-day ceasefire, Hamas released 24 of the roughly 240 hostages taken during its October 7 attack on Israel that triggered the war, and Israel freed 39 Palestinians from prison. Those freed in Gaza were 13 Israelis, 10 Thais and a Filipino.

Israel Palestinians
A person holds a placard with pictures of hostages held in the Gaza Strip, in Tel Aviv, Israel on Saturday (AP/Leo Correa)

On Saturday, Hamas provided mediators Egypt and Qatar with a list of 14 hostages to be released, and it has been passed to Israel, according to a Egyptian official speaking on condition of anonymity because he was not permitted to talk about details of the ongoing negotiations.

A second official, also speaking on condition of anonymity, confirmed the details. The head of Egypt’s government press office and the state-run Qahera news outlet said 13 hostages would be exchanged for 39 prisoners.

Under the truce agreement, Hamas will release one Israeli hostage for every three prisoners freed. Israel’s Prison Service said earlier Saturday it was preparing 42 prisoners for release. It was not immediately clear how many non-Israeli captives may also be released.

Overall, Hamas is to release at least 50 Israeli hostages, and Israel 150 Palestinian prisoners, during the four-day truce — all woman and minors.

Israel has said the truce can be extended an extra day for every additional 10 hostages freed — something US President Joe Biden said he hoped would occur.

Separately, a Qatari delegation arrived in Israel on Saturday to co-ordinate with parties on the ground and “ensure the deal continues to move smoothly”, according to a diplomat briefed on the visit. The diplomat spoke on condition of anonymity because he was not authorised to discuss details with the media.

The start of the pause brought the first quiet for 2.3 million Palestinians reeling from relentless Israeli bombardment that has killed thousands, driven three-quarters of the population from their homes and levelled residential areas. Rocket fire from Gaza militants into Israel went silent.

For the first time in more than a month, aid reached northern Gaza. The Palestinian Red Crescent said 61 trucks carrying food, water and medical supplies headed there on Saturday, the largest aid convoy to reach the area yet.

The UN said it and the Palestinian Red Crescent were also able to evacuate 40 patients and family members from a hospital in Gaza City, where much of the fighting has taken place, to a hospital in Khan Younis.