A senior Iranian security official denied on March 23 that any negotiations were underway with the United States, directly contradicting President Trump's claim hours earlier that the two sides had held "productive conversations," Tasnim reported.

"There are no negotiations and there have been no negotiations," the official said.

"Trump retreated from attacking critical infrastructure because Iran's military threats became credible," he added.

The statement reframes the five-day pause announced by Trump not as the product of diplomacy but as an American capitulation forced by Iran's warnings that any strike on power plants would trigger the "irreversible" destruction of Gulf energy infrastructure.

The official said financial market pressure and threats to the US bond market were also key factors behind the reversal.

"Trump's five-day ultimatum means the continuation of this regime's programme of crimes against our people, and we will continue our broad defence of the country," the official said.

The competing claims leave the situation deeply uncertain. Trump told the world talks were underway and ordered a pause. T

ehran says no such talks exist and that the pause was a forced retreat. Markets, which had been hoping for an off-ramp, face the prospect that neither side's version may be entirely true and that the conflict could escalate again within days.

Israeli jets were also reportedly striking Tehran and other locations across Iran on March 23, following the announcement by Trump, according to videos seen by IntelliNews. 

Earlier, Belarus's President Alexander Lukashenko has offered to mediate between the United States and Iran, presenting a peace plan to a visiting American delegation on March 19 and disclosing on March 20 that he had transmitted the proposal to the Trump administration, Belarussian media reported.

The five-day window, if it holds, expires on March 28.