A US-backed plan to end the war in Gaza was moving into its second phase, Washington's top negotiator said on Wednesday, as Palestinian factions agreed on the make-up of a post-war governing committee.

US President Donald Trump's envoy Steve Witkoff wrote on X that phase two of the US leader's 20-point plan would shift the Palestinian territory "from ceasefire to demilitarisation, technocratic governance and reconstruction."

Phase one, launched in October, involved a ceasefire, a hostage-prisoner exchange, partial Israeli withdrawal and a surge of humanitarian aid.

Under the second phase, Gaza would be run by a 15-member Palestinian technocratic committee supervised by a so-called "Board of Peace", to be chaired by Trump himself.

Egypt said all the members of the committee had been agreed upon by all Palestinian factions, which swiftly offered their support.

Ali Shaath, former Palestinian deputy minister in the Palestinian Authority, was named to lead the body, according to a joint statement by mediators Egypt, Turkey and Qatar.

The mediators did not disclose the remaining names.

Speaking at a press conference in Cairo, Egyptian Foreign Minister Badr Abdelatty said he hoped the committee would soon be deployed to Gaza to "manage daily life and essential services."

In a technical and detail-oriented interview on Palestinian Basma Radio on Wednesday, Shaath spoke at length on rebuilding the Gaza Strip, ravaged by more than two years of war and intensive bombing.

"We will set plans for water, well rehabilitation, water purification, and treated water – water is the secret to health, education, hospitals, all of which were destroyed," he added.

On the question of the vast amounts of rubble left from Gaza's destroyed buildings, Shaath floated the idea of pushing it into the adjacent Mediterranean to reclaim land.

"We are not talking about 'reconstruction' but construction anew," he said, highlighting the immediate need for shelter for Gaza's 2.2 million residents, almost all of whom have been displaced at least once during the war.

Regarding his jurisdiction, Shaath said that under the terms of the US-brokered agreement, his committee would gradually take over 50 percent of Gazan territory currently under Israeli control, before expanding to cover the entirety of its area.

He added that security and coordination with armed groups were not part of the committee's mandate.

"The commission is not an army; it is 15 Palestinian experts in reconstruction, assisted by staff – brains more than weapons," he said.

Palestinian factions, including Hamas and its ally Islamic Jihad, said they would support the committee and would help create "the appropriate environment" for it to begin its work.

Hamas has said it does not seek a role in any future governing authority in Gaza, and would limit its role to a monitoring capacity. (AFP)