On a whirlwind tour of the Middle East, Donald Trump announced the end of the war in Gaza on Monday as Hamas freed 20 Israeli hostages.

The first phase of the peace deal is underway, but despite the celebratory mood, experts warned that the ceasefire hangs by a thread, with the future uncertain as Hamas must still fulfill critical demands.

Most notably, the full return of the bodies of Israeli hostages.

The 20 remaining living hostages were released on Monday morning, followed by the remains of four others.

But the bodies of 24 hostages, which Hamas promised to release as part of the peace deal, are still unaccounted for. 

Lianne Pollack-David, former senior advisor to Israeli Prime Minister Benjamin Netanyahu, says the most critical test lies ahead. Trump’s peace deal risks complete collapse if Hamas fails to return the bodies of all deceased Israeli hostages, she says.

The Hostages and Missing Persons Families Forum, an Israeli advocacy group, warned that Hamas is already in ‘blatant breach’ of the peace agreement after it failed to release all of the remains today. 

Pollack-David, who previously negotiated with Palestinians, described the current phase of the deal as dangerously unstable, with the Israel Defense Forces having partially withdrawn to what is called the ‘yellow line’ –– about a 50 percent pullback.

President Trump visiting the country hours after Hamas released the remaining Israeli hostages 

Inbar Hayman (left), an Israeli hostage, and Joshua Loitu Mollel, a Tanzanian hostage, who have both died while being held in Gaza 

Itay Chen’s (left) remains are still believed to be in Gaza. Tamir Nimrodi (right), who was not among those freed today, is feared dead in Gaza

Photo by URMAN/SIPA/Shutterstock: Israel and Hamas agree to the first phase of Gaza ceasefire deal and people and hostages family wait for the return of the Hostage square in Tel Aviv

If Hamas violates the terms, that retreat could be reversed rapidly. 

She emphasized that Trump’s agreement is not a peace deal, but a shaky ceasefire with terrorists which was only in its initial phase. Much is unresolved.

Pollack-David says Hamas has already shown signs of defiance, including using psychological tactics to maintain a sense of control.

She says Hamas called the parents of these hostages and let them speak to their loved ones, because they wanted to let them know they maintain control over them. 

‘I don’t expect Hamas to come out in the next few days or months waving a white flag. They will do whatever they can to survive, and they’re already playing these tricks,’ the Netanyahu insider said. 

She added, ‘What they do next could blow up the whole deal.’

Pollack-David praised Trump’s strategic approach in the region, noting that he has effectively compelled regional actors such as Qatar, Turkey and Egypt to take concrete responsibility for Gaza’s future, rather than remaining passive observers.

Gaza, she argued, cannot remain solely Israel’s problem.

Released Israeli hostage Avinatan Or greets well–wishers upon arriving at Beilinson Hospital in the Rabin Medical Centre in Petah Tikva in central Israel 

Released hostage Avinatan Or, who was kidnapped during the deadly October 7 attack by Hamas and taken to Gaza, reacts upon arrival at the site of Rabin Medical Center–Beilinson Hospital, amid a hostages–prisoners swap and a ceasefire deal between Israel and Hamas in Gaza, in Petah Tikva, Israel October 13

Israeli soldiers salute as vehicles transporting the bodies of four hostages handed over following a ceasefire and prisoner exchange deal between Israel and Palestinian factions in Gaza, arrive to the National Center for Forensic Medicine in Tel Aviv on October 13

‘What President Trump did very smartly is put a lot of responsibility on the regional players… instead of just talking, he’s telling them, put your skin in the game,’ she said. 

At the same time, she expressed concern that key players like Saudi Arabia and the United Arab Emirates, who she identifies as representatives of a moderate and forward–looking Middle East, have so far played a limited role in the process.

‘Qatar and Turkey are now heavily involved, but there are big question marks. They’ve been strong supporters of the Muslim Brotherhood and Hamas, and very anti–Israel,’ she explained.

In the end, she said that United States, rather than the current Israeli government, will be the one who will decide if the war has ended.

‘The US will be the judge of long term peace. I wish it were Israel, but it can’t happen with this current government that mixes ultra-right wing ideology with security considerations. It doesn’t fully represent the Israeli public or Israel’s best long-term security interests,’ she said.

‘Trump’s vision at this moment is the right one. He’s pushing Israel in a direction that may not be convenient to everyone, but it’s necessary,’ she said.