Negotiators for the US and Iran have agreed a framework of a deal that would extend their ceasefire for 60 days and launch negotiations on the future of Iran's nuclear programme, US sources say.
US sources told the BBC that the new ceasefire agreement has not yet been approved by the leadership of either country.
The deal comes amid renewed attacks in the region, with Iran's Islamic Revolutionary Guard Corps (IRGC) saying it targeted an American air base in the region, after fresh US strikes on southern Iran overnight.
Both Iran and the US have accused each other of violating the fragile ceasefire in the past few days.
On Wednesday, Iranian state media reported elements of what they described as an unofficial draft of a 14-point memorandum of understanding (MOU).
The report included the lifting of Washington's naval blockade of Iranian ports, the withdrawal of US forces from the "vicinity of Iran", and the restoration of non-military traffic through the Strait of Hormuz with Iran and Oman in control of the management and routing of vessels.
One-fifth of the world's liquefied natural gas and oil normally pass through the shipping channel, and its closure has impacted global fuel trade.
The White House issued a terse statement, calling the purported MOU draft a "complete fabrication".
Both sides signalled progress had been made towards a deal late last week, prompting speculation an announcement was close.
Since the initial ceasefire between the US and Iran came into effect on 8 April, Trump has suggested - repeatedly - that the two sides are close to a deal and that negotiations are progressing, only to have any hopes of a negotiated end to the conflict dashed.
Talks that took place in Islamabad just days later, for example, ended without any substantive agreement.
In nearly every case, and as recently as Wednesday, Trump and other officials have warned that "option B", a return to combat operations, remains on the table.
Just last week, Trump told reporters that he had been an hour from ordering renewed strikes on Iran but ultimately held off at the request of US allies.
In a cabinet meeting on Wednesday, Trump said that talks were progressing but insisted that the Iranian proposal was "not there yet" and that work remained.
It is unclear what took place in the subsequent 24 hours, or when - or even if - Trump will give his final approval for the agreement to extend the ceasefire.
Doing so, however, would allow US and Iranian teams to discuss the far more complicated and technical issues at play, particularly about Iran's nuclear programme and its remaining stockpile of highly enriched uranium.
Trump had suggested that that US could take it, or, together with Iran, dilute it in place or in a third location.
Axios, which first reported the tentative agreement on Thursday, said that Trump had been briefed on the proposal but did not immediately sign off on it and would take a couple of days to consider it.
The confirmation from US sources of anonymously sourced Axios reporting on the contours of the agreement is rare, suggesting that the two sides may be closer to a deal than they were at any previous point during the more than six-week-old ceasefire.
Reports say the deal could allow "unrestricted" passage through the Strait of Hormuz, and that Iran would have 30 days to remove mines from the narrow shipping passageway.
The US would also lift its blockade, and issue sanction waivers to allow Iran to resume selling oil.
