Gaza's civil defence agency said a series of Israeli air strikes on Thursday killed at least 58 people, including 12 guards securing aid trucks, while the military said it targeted militants planning to hijack the vehicles.

The latest bloodshed came despite growing optimism that negotiations for a ceasefire and hostage release deal might finally succeed, with US National Security Adviser Jake Sullivan saying on Thursday that the regional "context" had changed in favour of an agreement.

G7 leaders will meet virtually Friday to discuss the momentous changes underway in Syria, where the interim government has vowed to institute the "rule of law" after years of abuses under ousted president Bashar al-Assad.

Assad fled Syria after a lightning offensive spearheaded by the Islamist Hayat Tahrir al-Sham (HTS) group and its allies, which brought a sudden end to five decades of repressive rule by his clan.

Almost a decade ago, a Syrian refugee's selfie with Germany's then chancellor Angela Merkel went viral. Today, Anas Modamani has a job, a German passport and a fiancee and no plans to return to his war-ravaged country.

While right-wing politicians in Europe have been quick to demand that Syrians "go home" after the fall of president Bashar al-Assad, Modamani's story typifies how many have put down roots in their host countries.

US Secretary of State Antony Blinken and Jordan's King Abdullah II called Thursday for a secure Syria as the top US diplomat began a regional tour following the overthrow of Bashar al-Assad in Damascus.

Blinken, who is heading to Turkey next, has called for an "inclusive" process to form Syria's next government that includes protections for minorities after Islamist-led rebels ended the repressive rule of Assad.

Gaza's civil defence agency reported that Israeli air strikes on Thursday killed at least 33 people, including 12 guards securing aid trucks in southern parts of the Palestinian territory.

The latest bloodshed occurred just hours after the UN General Assembly called for an immediate ceasefire in the devastated territory.

Seven guards were killed in a strike in Rafah, while another attack left five guards dead in Khan Yunis, agency spokesman Mahmud Basal said.

The Israeli military did not immediately respond to enquiries about the two strikes.

Riyad Avlar spent 20 years languishing in Syria's jails, including a decade in the infamous Saydnaya prison, the scene of some of the Bashar al-Assad government's most brutal abuses.

Those long years behind bars have left him with one obsession: documenting and healing the atrocities committed inside the prison where he himself was locked up.

"I am sure we'll see Bashar al-Assad in court one day," predicted Avlar, who is Turkish.

Israel has been accused of carrying out a "massacre" of journalists in Gaza in two separate reports from media freedom organisations this week that analysed the deaths of reporters worldwide this year.

According to calculations from Paris-based Reporters Without Borders (RSF) published on Thursday, the Israeli army killed 18 journalists as they were working this year —- 16 in Gaza and two in Lebanon -- around a third of the total worldwide of 54.

The surrender of the Mazzeh air base outside Syrian capital Damascus by Bashar al-Assad's forces triggered a round of Israeli air strikes designed to prevent his former arsenal falling into the hands of Islamist rebels.

But it also allowed a Syrian former detainee to revisit the ordeal he suffered at the hand of Assad's ousted forces.

The president's long and brutal rule came to a sudden end last week, and on Wednesday young rebels were roaming Mazzeh, periodically firing an old Soviet-designed anti-aircraft gun into the sky.

Shortly before Sunni Islamist-led rebels swept into the Syrian capital, Iran-backed guards fled their positions at the gates a revered Shiite shrine in a Damascus suburb.

By Wednesday, the few visitors in the area cast worried glances at the new guards of the Sayyida Zeinab shrine in the suburb of the same name, long known as a stronghold of pro-Iran fighters including Lebanon's armed group Hezbollah.

"On Saturday night, the Hezbollah fighters began to leave," said Walid Haji, 45, an armed rebel posted to a checkpoint previously held by the Lebanese group.

Egyptian President Abdel Fattah al-Sisi met his Irish counterpart Michael Higgins and prime minister Simon Harris Wednesday for talks on the war in Gaza and boosting bilateral ties.

The two heads of state discussed the Middle East situation, including the political upheaval in Syria, according to a statement from Higgins's office.

"The outrageous suffering in the absence of a ceasefire in Gaza was the central part of their discussion," the statement added.