Trump stunned the world earlier this year when he suggested the United States should take control of the Gaza Strip, clear out its inhabitants and redevelop it as seaside real estate.
Israeli Prime Minister Benjamin Netanyahu praised the proposal, which sparked a global outcry.
Witkoff in his interview accused Hamas of having “slow-played” the negotiations process. Senior Hamas official Izzat al-Rishq accused Witkoff of echoing “Netanyahu and his government of war criminals”.
In Gaza City’s Zeitoun neighbourhood on Wednesday, residents reported heavy Israeli bombardment overnight.
“Some neighbours have fled … But wherever you flee, death follows you,” said Tala al-Khatib, 29.
Zeitoun resident Abdel Hamid al-Sayfi, 62, said he had avoided going outside.
“Whoever steps outside is fired upon by the drones,” he told AFP.
Media restrictions in Gaza and difficulties in accessing many areas mean AFP is unable to independently verify the tolls and details provided by the civil defence agency or the Israeli military.