A senior U.S. official told ABC News on Thursday that the call from President Joe Biden, the ‎‏Egyptian President and the Qatari Amir for Israel and Hamas to return to the negotiating table to work out a cease-fire deal was a step forward, despite more work needing to be done.

"It's not like the agreement is going to be ready to be signed on Thursday," the official said. "There's still a significant amount of work to do, but we do believe that what's left here really can be bridged, and there's really just no time to lose," the official added.

The official said that both Israel and Hamas have "very firm positions" on "about four or five issues" each. And though the official said they might seem to be "unbridgeable," they have been able to find a way forward working through the issues one by one.

"We are determined to do all that we possibly can, recognizing that lives are on the line," the official added.

-ABC News' Michelle Stoddart

In a joint statement, leaders from the U.S., Egypt and Qatar called on Israel and Hamas to resume discussions on Gaza.

The statement -- signed by President Joe Biden, Egyptian President Abdel Fattah el-Sisi and Amir Sheikh Tamim Bin Hamad Al-Thani of Qatar -- called for both sides to meet in Doha or Cairo on Aug. 15.

"‎‏It is time to bring immediate relief both to the long-suffering people of Gaza as well as the long-suffering hostages and their families," the statement read. "The time has come to conclude the ceasefire and hostages and detainees release deal."

At least 39,755 Palestinians have been killed in Gaza since Oct. 7, according to the Hamas-run Gaza Health Ministry.

On Oct. 7, about 1,200 Israelis were killed and more than 200 were taken hostage.

Five Israel Defense Forces soldiers who are in custody under suspicion of aggravated abuse of a Palestinian prisoner have been denied release by a military court on Thursday, according to the IDF.

The Military Court of Appeals approved the detention of the suspects until Sunday, stating that from the evidence presented, there is "reasonable suspicion of the commission of the acts attributed to them. The military court also determined that there was a clear cause of danger from the attributed acts," the IDF said.

United Nations experts have called the reported widespread torture of Palestinian detainees a "preventable crime against humanity."

"Reports of alleged torture and sexual violence in Israel’s Sde Teiman prison are grossly illegal and revolting, but they only represent the tip of the iceberg, independent human rights experts warned," U.N. experts said on Tuesday.

Around 9,500 Palestinians, including hundreds of children and women, are currently imprisoned -- about one-third of them without charge or trial, according to the U.N.