US envoy Steve Witkoff has announced the start of phase two of President Donald Trump's plan to end the war in Gaza, with a technocratic Palestinian government established in the territory.

He said the second phase would also see the reconstruction and full demilitarisation of Gaza, including the disarmament of Hamas and other Palestinian groups.

The US expects Hamas to comply fully with its obligations, he warned, noting these include the return of the body of the last dead Israeli hostage. Failure to do so will bring serious consequences.

Under phase one, Hamas and Israel agreed a ceasefire in October, as well as a hostage-prisoner exchange, a partial Israeli withdrawal, and an aid surge.

Following the US announcement, regional mediators Egypt, Gaza and Turkey welcomed the formation of what they called the Palestinian Technocratic Committee to Administer the Gaza Strip, saying it would contribute to strengthening efforts aimed at consolidating stability and improving the humanitarian situation.

They also revealed that the 15-member body would be headed by Ali Shaath, a former deputy planning minister in the Western-backed Palestinian Authority (PA), which governs parts of the occupied West Bank not under Israeli control.

The transitional administration will operate under the supervision of a Board of Peace, which will be chaired by Trump, according to the 20-point plan he unveiled three months ago.

Announcements related to the board are expected in the coming days, including when the president visits the World Economic Forum in Davos next week.

Former UN Middle East envoy Nickolay Mladenov, who has been meeting Israeli and Palestinian officials, is set to be the board's representative on the ground in Gaza.

Earlier on Wednesday, Hamas and its ally Palestinian Islamic Jihad (PIJ) said in a joint statement that they had agreed to support the efforts to form the technocratic Palestinian government while providing the appropriate environment for it to begin work.

The PA - which is dominated by Fatah, Hamas's rival - also expressed its support.

Vice-President Hussein al-Sheikh said Trump's leadership had contributed to creating a new opportunity for peace, stability, and good governance, and urged all Palestinian factions, institutions and segments of society to ensure the success of this critical transitional phase.

The office of Israel's prime minister meanwhile said he had spoken on Wednesday evening with the parents of Ran Gvili, the last dead hostage in Gaza.

Benjamin Netanyahu made it clear to Itzik and Talik Gvili that Ran's return is our top priority and that the declarative move to establish a technocratic committee will not affect efforts to return Ran for burial in Israel, his office added.

The 24-year-old police officer was among the 251 people abducted during the Hamas-led attack on southern Israel on 7 October 2023, when about 1,200 other people were killed.

Israel responded to the attack by launching a military campaign in Gaza, during which more than 71,430 people have been killed, according to the territory's Hamas-run health ministry.