Israel and Palestinian militant group Hamas have raised concerns over the lists of Israeli hostages and Palestinian prisoners due to be released on Monday, the final day of an agreed four-day pause in the fighting, an official briefed on the matter said, Reuters reported.

The official, speaking on condition of anonymity, told Reuters that Qatari mediators were working with Israel and Hamas to resolve the issues and avoid delays.

Hamas said it wanted to extend the truce. An Israeli official reiterated on Monday Israel’s position that it would agree to an additional day of truce for each additional 10 hostages freed and to release three times the number of Palestinians each time.

“There is a slight issue with today’s lists. The Qataris are working with both sides to resolve it and avoid delays,” the official briefed on the matter said.

Israel said earlier it had received overnight what could be the final list of hostages due for release. The list was being reviewed, Prime Minister Benjamin Netanyahu’s office said, adding it would provide further information when possible.

On Sunday, Hamas freed 17 people, including a 4-year-old Israeli-American girl, bringing the total number the militant group has released since Friday to 58. Israel released 39 teenage Palestinian prisoners on Sunday, taking the total number of Palestinians freed since the truce began to 117.