They included a possible $300 billion reconstruction fund for the war-battered country, but the release of funds will be "tied to performance," a senior Trump administration official said in a call with reporters.

Trump, US Vice President JD Vance and Iranian parliament speaker Mohammad Bagher Ghalibaf electronically signed the deal on Sunday, the officials said.

"The president wanted to sign it personally because he wanted to show his dedication to the process," one of the US officials said on condition of anonymity.

Technical talks led by Vance will begin this week before the deal is formally signed on Friday in a ceremony that is expected to be held in Geneva, Switzerland.

Vance, Trump's son-in-law Jared Kushner and Middle East Special Envoy Steve Witkoff will attend the signing, the officials said.

Questions swirled while Trump attended a G7 summit in France, with the wording of the so-called memorandum of understanding still unclear.

Trump said the text would likely be released after the signing on Friday -- but the US officials said it would be "put out in the next 24-48 hours."

- Hormuz normal in 'couple of weeks'? -

The signing will kick off a 60-day period in which Iran and the United States will try to hammer out a full-scale peace deal, including the thorny issue of Iran's nuclear program.

"We want to put the nuclear discussions up front," a US official said on the call.

But the bottleneck in the Strait of Hormuz is an immediate priority due to the global economic effects from the spike in oil prices.

Vance told CNBC there was an understanding with Iran that the strait would reopen "in a toll-free way for the long term, and that's the sort of thing that we're going to figure out in these technical negotiations."

Trump himself said the critical bottleneck would be "completely open" from Friday but added that there was still "hunting" going on to ensure that it was de-mined.

Shipping traffic should return to pre-war levels "over the next couple of weeks" but there had already been a "substantial increase in traffic," the first US official said.

However, Iran's foreign ministry said on Monday that the deal would allow it to charge maritime service fees on ships transiting the Strait of Hormuz, rather than imposing "tolls."

- 'Zero' funds released -

Uncertainty also surrounds other key aspects of the deal, including Iran's access to its frozen funds and relief from international and US sanctions.

The issue is politically sensitive for Trump because he has alleged that an Iran deal signed under Democratic president Barack Obama -- which Republican Trump scrapped in 2018 -- gave Tehran too much money.

"The very simple fact is zero dollars of frozen assets have been released by the United States or any other country," the first US official said.

"We discussed the possibility of releasing frozen funds, sanctions relief, a big $300 billion fund to rebuild their country, and all of these things are going to be tied to performance," added the second official.

The US officials also lashed out at former mediator Oman, which sits on the other side of the Strait of Hormuz from Iran, and which Trump threatened to bomb last month.

"We were very unhappy with the job the Omanis did,"the second official said. "We felt they were very duplicitous, almost like employees of the Iranians."