US Vice President JD Vance landed in Israel yesterday to shore up a fragile Gaza ceasefire deal, after President Donald Trump warned Hamas it would be wiped out if it breached the truce.

Trump's special envoy Steve Witkoff and son-in-law Jared Kushner were already in Tel Aviv, where they met Israeli hostages released by Hamas after two years of captivity in Gaza.

"Welcome to Israel, Vice President Vance," Israel's foreign ministry posted on social media, along with a photo of Vance and his wife stepping off the plane.

"Together, the Promised Land and The Land of the Free, can secure a better future, including the release of the remaining 15 hostages," it added.

Vance is to meet Witkoff, Kushner and US military experts monitoring the truce. According to Israeli media reports he will meet Israeli leaders, including Prime Minister Benjamin Netanyahu today in Jerusalem.

After Israel said Hamas killed two soldiers on Sunday and accused the group of stalling the handover of hostages' bodies, it unleashed a wave of strikes on the territory -- later saying it had "renewed enforcement" of the ceasefire.

The US is now redoubling efforts to cement the fragile Gaza deal Trump helped to broker.

"The dynamic keeps going back and forth," Mairav Zonszein, senior analyst on Israel for the International Crisis Group (ICG), told AFP.

"Trump is on the one hand letting Israel do what it wants, and on the other hand, at the end of the day, he wants the ceasefire to hold," she said.

"Netanyahu is playing both approaches... He's talking about peace and giving peace a chance... And at the same time, he's bombing Gaza and he's trying to condition aid again," she added.

Trump says he believes the deal is still holding and that Hamas militants understand what will happen if they breach it. "They'll be eradicated, and they know that," he told reporters at the White House.

Later, Trump threatened to "straighten out" Hamas with allied forces.

"I told these countries, and Israel, "NOT YET!" There is still hope that Hamas will do what is right. If they do not, an end to Hamas will be FAST, FURIOUS, & BRUTAL! I would like to thank all of those countries that called to help," Trump wrote on Truth Social.

Hamas has denied any knowledge of Sunday morning's deadly violence in the southern Gaza city of Rafah.

Israel responded after the soldiers' deaths with an intense wave of bombings, which the Hamas-run territory's health ministry said killed 45 Palestinians.

Egypt's intelligence head Hassan Rashad was also in Israel yesterday to reinforce the truce, according to Netanyahu's office and Egyptian state-linked media.

The spy chief will also meet with US envoy Witkoff, Extra News reported.

US ally and fellow truce mediator Qatar accused Israel of what its leader called the "continued violation" of the now 11-day-old ceasefire.

Hamas's Gaza leader, in Cairo for talks with Egypt and Qatar, issued a statement expressing confidence that the truce will hold.

"What we heard from the mediators and from the US president reassures us that the Israeli war on the Gaza Strip has ended," Khalil al-Hayya said.