US President Donald Trump's promise of "good" and "productive" talks with Iran are perhaps his most conciliatory remarks since the beginning of Operation Epic Fury, but leave significant unanswered questions.

Early on Monday morning - just hours before markets opened - Trump took to Truth Social, promising to hold off on striking Iranian power plants and energy infrastructure for a five-day period as talks continue, after having previously threatened to "obliterate" these targets unless Iran opens the Strait of Hormuz.

Iran, however, has denied that any contact between its official and the Trump administration has taken place.

This, in turn, immediately prompted questions on what talks Trump was referring to, or whether he was seeking to calm troubled global markets.

Speaking to reporters in Palm Beach, Trump said that both sides are looking to make a deal and that the US maintains a "great relationship" with a lot of potential partners in the Middle East, although he did not identify any.

While Trump said that special envoy Steve Witkoff and Jared Kushner, Trump's son-in-law, participated in the talks, Trump offered no details on who they were with, or what they were focused on.

Possibilities include opening the Strait of Hormuz, Iran's ballistic missile programme, the enrichment of uranium, or a simple ceasefire, a possibility which Trump had previously downplayed.

The US president has repeatedly told reporters that multiple tiers of Iranian leadership have been wiped out, and at a Friday event at the White House said that it is "hard to find leaders in Iran to talk to because they keep getting killed".

In a brief phone interview with CNBC reporter Joe Kernen following Trump's post on Monday morning, Trump said that Iran has representatives left, contradicting his own previous public statements.

He suggested that they are behaving differently than their predecessors. Kernen said that Trump was "insisting" that the change constitutes a form of regime change.

Iran's denial that any talks have taken place, however, complicates this narrative for the administration and will likely make for awkward questions.

Already, an unnamed Iranian source quoted by Fars News Agency, affiliated with Iran's Islamic Revolutionary Guard Corps (IRGC), characterised Trump's statement as something of a victory for the regime, claiming Trump "backed down" after Iran's threats to launch retaliatory strikes against energy infrastructure across the region.

The talks could also be something of a ruse - as was the case last summer when talks with the Iranians were reportedly still progressing right up until US bombs struck Iranian nuclear facilities during Operation Midnight Hammer.

Trump, after all, often reminds reporters that his decision-making process or thinking on a particular topic is a mystery to almost everyone.

Even with scant evidence of sustained negotiations, Trump's post led US stock market futures to rally and global oil prices to drop precipitously.

What was shaping up to be a dismal day for major world economies was left with a glimmer of optimism.

The timing of Trump's post – just before US markets open – may not have been a coincidence.

The president's threat to attack Iranian power facilities by Monday evening - after his deadline had passed - had led to widespread fears of an escalation in the war.

His decision to delay any action for five days has, for now, eased those concerns.

If talks did take place, it is not clear how serious any US-Iranian negotiations have been, whether the US and Israel will continue other airstrikes and whether Iran is still restricting access to the Strait of Hormuz - the reason for Trump's Monday bombing deadline in the first place.

This may be the first indication of a real breakthrough. Or it could be the move of a president who had put himself into a difficult spot looking for a way to buy himself more time.

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Energy prices fall and stock markets rebound after the US president says "very good and productive" talks have been held.

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