The US has proposed commanding a multinational force in postwar Gaza with troops from Albania, Indonesia, Kazakhstan, Kosovo and Morocco, as Donald Trump unveiled his ad-hoc Board of Peace in Washington to heavy international scrutiny.

The US plan would require the full disarmament of Hamas and support from Israel, which has tempered expectations that the Trump-friendly committee stacked with autocrats and rightwing allies will be able to deliver on the vision of ending the conflict and rebuilding Gaza as a “riviera”.

That did not stop the board from proposing a huge peacekeeping and reconstruction mission in Gaza at a madcap inaugural summit where the president of Kazakhstan, Kassym-Jomart Tokayev, mooted a Trump peace prize and the head of Fifa, Gianni Infantino, donned a red USA cap before unveiling a partnership with the $1bn-a-seat committee.

In opening remarks, Trump said the US would commit $10bn (£740m) to a fund to reconstruct Gaza – a small amount, he said, to “achieve the dream of bringing lasting harmony to a region tortured by centuries of war, suffering and carnage”.

Azerbaijan, Bahrain, Kazakhstan, Morocco, Qatar, Saudi Arabia and the United Arab Emirates would contribute $7bn collectively, the UN $2bn and Fifa, the world football coordinating body, $75m.

“We’re going to straighten out Gaza, we’re going to make Gaza very successful and safe,” Trump said as he gavelled out the meeting. “And we’re also going to maybe take it a step further where if we see hotspots around the world, we can probably do that very easily. This is a tremendous group of powerful people.”

Maj Gen Jasper Jeffers III, the US officer appointed to command the future international stabilisation force (ISF), said the board planned to deploy 20,000 soldiers in five different sectors of Gaza, beginning with Rafah.

He said its long-term objective was to deploy 12,000 police, with Egypt and Jordan committing to training officers in the future. Indonesia’s president, Prabowo Subianto, said his country was ready to commit as many as 8,000 troops “or more if necessary”.

The Guardian has revealed that the Trump administration plans to build a 5,000-person military base over more than 350 acres in Gaza, , according tothe board’s contracting records.

Aid workers have said an organisation established by the board, the National Committee for the Administration of Gaza, has been frustrated by a lack of direction and that an ISF office in the territory remains empty.

It is unclear what the ISF’s remit or rules of engagement would be, meaning the lack of a political solution would be likely to frustrate efforts to rebuild the territory.

Yakir Gabay, a Cypriot-Israeli billionaire heading the board’s planned reconstruction efforts, described plans to remove more than 70m tonnes of rubble and unexploded ordnance and develop the Gaza coastline into a “new Mediterranean Riviera with 200 hotels and potential islands”. The plan would all be subject to the full disarmament of Hamas, he said.

The board has been criticised as a shadow UN, and major European allies including the UK, France and Germany have declined to join it. The Vatican said this week that it would not take part.

The Israeli prime minister, Benjamin Netanyahu, who is under pressure from rightwing coalition allies to maintain a hardline position on Gaza, did not attend. His foreign minister, Gideon Sa’ar, emphasised Israel’s security concerns and said the plan included the “disarmament of Hamas and Islamic Jihad, demilitarisation of the Gaza Strip and deradicalisation of Palestinian society”. He said: “It’s the first plan to address the root of the problem.”

In his opening remarks, Trump repeated his hyperbole about resolving eight wars since entering power, riffed about how he was not supposed to endorse foreign candidates and then backed Hungary’s Viktor Orbán in upcoming elections. He also joked about his secretary of state, Marco Rubio, renaming the DC venue for the meeting the Institute of Peace in his honour.

The board met as the US has massed forces in the Middle East, including two aircraft carriers and dozens of warplanes, for a potential attack on Iran that could dwarf last summer’s US strikes on the country’s nuclear facilities.

Addressing world leaders and delegates mainly from the Middle East and Asia, Trump said the US had brought peace to the Middle East by launching strikes on Iran’s nuclear facilities and now “we’ll see where that goes”.

“Now we may have to take that a step further, or we may not,” he said. “Maybe we’re going to make a deal. You’re going to be finding out over the next probably 10 days.

“Good talks are being had … It’s proven to be, over the years, not easy to make a meaningful deal with Iran. We have to make a meaningful deal, otherwise bad things will happen. We have to make a meaningful deal.”