US President Donald Trump has given Hamas a deadline to accept a US peace plan for Gaza or face “all hell”.

Trump wrote on his Truth Social platform on Friday that an agreement must be reached by 18:00 Washington time (22:00 GMT) on Sunday.

The plan proposes an immediate end to fighting and the release within 72 hours of 20 living Israeli hostages held by Hamas – as well as the remains of hostages thought to be dead – in exchange for hundreds of detained Gazans.

Arab and Turkish mediators are understood to be pressing Hamas for a positive response to the proposal, but a senior Hamas figure has said the armed group is likely to reject it.

“If this LAST CHANCE agreement is not reached, all HELL, like no one has ever seen before, will break out against Hamas. THERE WILL BE PEACE IN THE MIDDLE EAST ONE WAY OR THE OTHER,” Trump wrote in the Truth Social post.

The deadline announced on Friday comes after Trump said on Tuesday that he was giving Hamas “three to four days” to respond to the peace plan.

Mediators have made contact with the head of Hamas’s military wing in Gaza, who has indicated he does not agree to the new US ceasefire plan, the BBC understands.

It is thought that some of Hamas’s political leadership in Qatar are open to accepting it with adjustments – but have found their influence limited as they do not have control of the hostages held by the group.

Another stumbling block for some in Hamas is that the plan requires them to hand over all of the hostages over the first 72 hours of the ceasefire – giving away their only bargaining chip.

There are believed to be 48 hostages still being held in the Palestinian territory by the armed group, only 20 of whom are thought to be alive.

The 20-point plan, agreed by Trump and Israeli Prime Minister Benjamin Netanyahu and announced by both at the White House on Monday, also says Hamas will have no role in governing Gaza, and leaves the door open for an eventual Palestinian state.

However, Netanyahu later reinstated his longstanding opposition to a Palestinian state, saying in a video statement shortly after the announcement: “It’s not written in the agreement. We said we would strongly oppose a Palestinian state,” he said.

The plan stipulates that once both sides agree to the proposal “full aid will be immediately sent into the Gaza Strip”.

It also outlines a plan for the future governance of Gaza, saying a “technocratic, apolitical Palestinian committee” will govern temporarily “with oversight and supervision by a new international transitional body, called the Board of Peace”, which it says will be headed by Trump.

• Read the full plan

European and Middle Eastern leaders have welcomed the proposal.

In a joint statement, the foreign ministers of the United Arab Emirates, Saudi Arabia, Qatar, Egypt, Jordan, Turkey, Indonesia, and Pakistan said they were ready to engage with the US to finalise and implement the agreement, which they said should lead to a “two state solution, under which Gaza is fully integrated with the West Bank in a Palestinian state”.

The Palestinian Authority (PA), which governs parts of the Israeli-occupied West Bank, has called the US president’s efforts “sincere and determined”.

Trump has said that if Hamas does not agree to the plan, Israel would have US backing to “finish the job of destroying the threat of Hamas”.

Netanyahu has also said Israel “will finish the job” if Hamas rejected the plan or did not follow through.

The Israeli military launched a campaign in Gaza in response to the Hamas-led attack on southern Israel on 7 October 2023, in which about 1,200 people were killed and 251 others were taken hostage.

At least 66,288 people have been killed in Israeli attacks in Gaza since then, according to the territory’s Hamas-run health ministry.