Tehran and Washington have been locked in a bitter standoff since last year when US President Donald Trump unilaterally pulled out of the deal that gave Iran relief from sanctions in return for curbs on its atomic programme.

At the height of the crisis in June, Iran shot down a US drone in the Gulf and Trump approved a retaliatory strike against the Islamic republic before cancelling it at the last minute.

"A delegation is going to France next week and they will negotiate... issues," said Mahmoud Vaezi, the chief of staff of Iran's President Hassan Rouhani.

"These negotiations have made relatively good progress since last week," Vaezi was quoted as saying by state news agency IRNA.

The newly announced visit comes after Iran's top diplomat Mohammad Javad Zarif travelled to France on Sunday for the second time in a matter of days.

Zarif held meetings on the sidelines of the G7 summit in Biarritz after which Trump said he was open to meeting his Iranian counterpart.

Rouhani has since played down the prospect of meeting Trump, however, saying the Americans would have to take the first step and lift all sanctions against Iran.

In response to the US withdrawal and its imposition of crippling sanctions, Iran has hit back by abandoning commitments under the nuclear deal known formally as the Joint Comprehensive Plan of Action (JCPOA).

French President Emmanuel Macron has been leading efforts to ease the situation, urging the United States to allow Iran to sell oil to China or India or give it access to a new line of credit.

Vaezi refused to reveal details on any package in his remarks on Wednesday.

"Until the issue is finalised, no details will be announced," he said, according to IRNA.

"What we have been doing with France... is restoring Iran's rights under the JCPOA and lifting unjust sanctions," he added.