Israeli officials have expressed cautious optimism at the prospect of a hostage deal, telling Israeli media that they believe a deal is close to being done.

According to reports from Reuters, Israeli officials say that a final hostage deal has been submitted by Qatar to senior Hamas officials for final approval. 

A breakthrough is believed to have been reached last night between Qatari mediators, the Israeli negotiators, and President-Elect Trump’s Middle East envoy. 

According to an outline published by Saudi outlet Al Arabiya, under the terms of the phased agreement Israel is to withdraw from specific areas of Gaza over 42 days, increase humanitarian aid and eventually withdraw fully from Gaza. The agreement also includes the release of 50 Palestinian terrorists serving life sentences and the exchange of 50 female prisoners for each Israeli woman released.

Meanwhile, US President Joe Biden spoke with Israeli Prime Minister Benjamin Netanyahu on the phone on Sunday.

The White House said Biden and Netanyahu "discussed the fundamentally changed regional circumstances following the ceasefire deal in Lebanon, the fall of the Assad regime in Syria, and the weakening of Iran’s power in the region."

Biden "stressed the immediate need for a ceasefire in Gaza and return of the hostages with a surge in humanitarian aid enabled by a stoppage in the fighting under the deal," the U.S. readout continued.

The Israeli leader was also said to have expressed gratitude to Biden for "his lifelong support of Israel and for the extraordinary support from the United States for Israel’s security and national defense."

According to the PMO, Netanyahu "thanked President Biden and President-elect Donald Trump for cooperating in this sacred mission."

"The prime minister discussed with the American president the progress in the negotiations to release our hostages and updated him on the mandate he gave to the negotiating team to Doha in order to advance the release of our hostages," the statement from Jerusalem added.

"We are very, very close and yet far, because we are not there,” US National Security Adviser Jake Sullivan told CNN earlier on Sunday when asked about a deal between Israel and Hamas for the retrieval of the dozens of hostages being held in Gaza.

“It is possible to get it done before January 20, but I can’t be sure," Sullivan said, reiterating the mix of optimism and caution that Biden and Secretary of State Antony Blinken shared in their comments last week on the talks' progress.

On Saturday, Netanyahu sent his most senior negotiators—including Israel Security Agency (Shin Bet) head Ronen Bar, Mossad Director David Barnea and Maj. Gen (res.) Nitzan Alon, the IDF’s point man for retrieving the hostages—to Doha, indicating that the discussions are approaching a critical point.

Among the hurdles that blocked previous rounds of talks were Hamas’s insistence on an IDF withdrawal from the Gaza Strip as a precondition to releasing the hostages and its demand for the release of terrorists in Israeli prisons that Israel is not prepared to set free.

Trump has warned Hamas to release the hostages before he enters office on January 20, promising that there will be “hell to pay” if this does not happen.