"The Americans must understand that bellicosity and warmongering don't work in their favour. Both... must be abandoned," Rouhani told a meeting of his cabinet in remarks aired on state television.

"The enemy imposed 'maximum pressure' on us. Our response is to resist and confront this."

Arch-foes Tehran and Washington have been at loggerheads since May last year when US President Donald Trump unilaterally withdrew from a 2015 nuclear deal and began reimposing crippling sanctions.

Iran has riposted by scaling back its nuclear commitments in response to the US withdrawal from the deal, which gave it the promise of relief from sanctions in return for curbs on its atomic programme.

In his remarks on Wednesday, Rouhani said Iran was ready to comply with the Joint Comprehensive Plan of Action only if the Americans did so too.

"We have said many times that our policy... is one of peaceful (nuclear) technology, and that our approach in the JCPOA is commitment for commitment," he said.

"We have taken the third step... If it is essential and necessary in the future, we will take other steps," he added.

Iran said on Saturday it was firing up advanced centrifuges to enrich uranium at a faster rate -- its third step in reducing its commitments to the 2015 nuclear deal.

It had already hit back twice before with countermeasures in retaliation for the US withdrawal from the accord.

On July 1, it said it had increased its stockpile of enriched uranium to beyond the 300-kilogram maximum set by the deal.

A week later, it announced it had exceeded a 3.67-percent cap on the purity of its uranium stocks.