"I can tell you that Iran wants to meet," he told reporters at the White House.

Trump has repeatedly indicated he is ready to meet with President Hassan Rouhani, who is expected to attend the UN General Assembly in New York this month. However, the Iranians have so far not given a positive response.

On Wednesday, Rouhani blasted the Trump administration, which has poured pressure on Iran, saying "the Americans must understand that bellicosity and warmongering don't work in their favor. Both... must be abandoned."

Arch-foes Tehran and Washington have been at loggerheads since May last year when Trump withdrew from a 2015 nuclear deal and began reimposing punitive measures.

Iran responded by scaling back its commitments to the accord, which gave it the promise of sanctions relief in return for curbs on its nuclear program.

However, some analysts see hope for more compromise following this week's exit of Trump's hardline national security adviser John Bolton, who in the past has called for the use of military force and regime change.

Bolton's departure came just days after Iran announced it had fired up centrifuges to boost its enriched uranium stockpiles in another step back from the deal.

Hesameddin Ashena, an adviser to Rouhani, hailed Bolton's dismissal as "a clear sign of the defeat of America's maximum pressure strategy."

Yet even with Bolton gone, top Trump officials have shown no signs of backing down from the strategy of sanctions against Iran.

"Now the president has made clear he is happy to take a meeting with no preconditions, but we are maintaining the maximum pressure campaign," Treasury Secretary Steven Mnuchin said after Bolton's departure.

The idea of a Trump-Rouhani meeting was floated last month by French President Emmanuel Macron, who has been spearheading European efforts to de-escalate tensions.

Rouhani said in response that Iran was ready to comply with the nuclear deal, known as the Joint Comprehensive Plan of Action, only if the Americans did so too.