* Agreement struck in June has swiftly unravelled

* Both sides accuse each other of failing to stick to terms

* Strait of Hormuz remains closed

* Attacks on shipping on Tuesday rattled markets again

By Parisa Hafezi and Elwely Elwelly

DUBAI/WASHINGTON, Aug 12 (Reuters) - Iran and the United

States remain at loggerheads over efforts to agree a permanent

end to the war in the Gulf, according to a senior Iranian

source, who said there had been no progress in talks to revive

the interim deal agreed in June and define a time frame to

implement it.

The comments came as U.S. President Donald Trump issued yet

another broadside against Iran's leaders, dealing a further blow

to hopes for a resolution to the crisis, following new attacks

on shipping in the region on Tuesday.

The deal agreed in June declared an "immediate and permanent

termination of military operations on all fronts", but quickly

unravelled, with Trump saying it was "over" on July 7 and Iran's

foreign ministry declaring it "suspended" a week later.

The U.S. accuses Iran of failing to honor an agreement under

the deal to reopen the vital Strait of Hormuz shipping route.

Tehran says Washington has reneged on its commitments, including

lifting a blockade of Iranian ports and releasing frozen Iranian

assets.

"One of the issues that is being discussed via mediators is the

U.S. returning to the interim agreement and defining a time

frame for implementing the commitments. There has been

absolutely no progress on this issue," the Iranian source said.

Trump said on Wednesday that the U.S. has "total control"

over the Strait of Hormuz.

But the Persian Gulf Strait Authority, the body Iran set up

to ‌manage the waterway, said it remains blocked and will not be

reopened until Iran's conditions are accepted.

"Iran is all talk and no action, the Bully of the Middle

East No Longer," Trump said on his Truth Social platform.

Throughout the conflict, Trump has alternated between threats of

escalation and claims that a peace deal is imminent.

'NO TALK OF EXTENSION'

Thousands of people have been killed in the conflict, mainly

in Iran and Lebanon, since the U.S. and Israel launched attacks

on Iran on February 28.

Iran has struck U.S. assets and infrastructure in countries

including Oman, Jordan, Kuwait, Israel, the United Arab Emirates

and Saudi Arabia.

The June interim ceasefire agreement set a 60-day period,

extendable by mutual consent, within which Iran and the U.S.

were expected to reach a final deal limiting Tehran's nuclear

program and lifting U.S. sanctions.

The Iranian source dismissed a report on Wednesday from

Turkey's Anadolu news agency that quoted Pakistani government

sources as saying they had agreed to extend that 60-day period.

"There is no talk of an extension because, from Iran's

perspective, there is no period that began and therefore nothing

to extend. The United States violated the interim agreement 48

hours after it was reached and withdrew from it a few days

later," the source told Reuters.

ATTACKS ON SHIPPING

The Strait of Hormuz, a narrow waterway between Iran and

Oman and the entrance to the Gulf, handled a fifth of global oil

and liquefied natural gas flow before the war.

Benchmark Brent crude futures have surged since the

start of the war in February, hitting a peak of $126 a barrel,

roughly 75% above pre-war levels, with choppy trade reflecting

concerns over disruptions to Gulf oil supplies and shifting

signals on peace talks.

On Tuesday, in separate incidents, a suspected Houthi attack

on a small cargo vessel killed four crew members in the Bab

el-Mandeb Strait and a U.S. Navy MH-60 helicopter fired two

Hellfire missiles to disable the steering gear of a

Panama-flagged cargo ship, the U.S. military said.

Oil prices rose but then steadied in volatile trading on

Wednesday, after forecasters cut projections for 2026 oil

demand. Brent crude futures were trading at ​around $88 a barrel

and U.S. West Texas Intermediate crude at around $83 a barrel.