German Chancellor Angela Merkel said that talks between Iran and France were "parallel" but not officially part of the G7 Summit.
Comment from French foreign minister came after President Trump accused President Macron of sending 'mixed signals' to Tehran.
Fariba Adelkhah, a researcher in anthropology and social sciences at Paris-based Sciences Po institute, is thought to have been arrested in June.
French foreign minister Jean-Yves Le Drian told a French parliament foreign affairs committee that, as long as Tehran respects the 2015 deal restricting its nuclear technology programme from military use, Paris will agree to resuming an exchange of ambassadors after a diplomatic freeze caused last year over an alleged Iranian plan to attack opponents of the ruling regime in France.
French oil and gas giant Total has been handed a 500,000-euro fine after it was found guilty of bribing officials in Iran to gain access to a gas field in the country in a deal dating back to 1997.
Paris freezes assets of suspected Iranian intelligence operatives as Tehran denies involvement in plan against exiled opposition group.
Under threat of US sanctions Total has officially halted its multi-billion-dollar investments into a gas production project in Iran, while carmakers PSA, Renault and Daimler are also among those to suspend or drop plans to invest in the country, along with Deutsche Bahn and Deutsche Telekom.
The men, including an Iranian diplomat,will face claims they were involved in a plot to bomb an Iranian opposition rally on the outskirts of Paris.
Four people held for allegedly plotting bombing of rally by MEK - a fringe group loathed in Tehran - attended by Trump lawyer Rudy Giuliani.
France's economy minister Bruno Le Maire has said he hoped the European Union would step in to compensate companies from among its member states who are targeted by sanctions which US president Donald Trump intends to introduce against firms doing business with Iran.
The company said it will end work on major South Pars 11 gas field project it began in July 2017 unless it is exempted.
French president’s offer seems calculated to appease US president's discontent with the current ‘bad deal’ on Iran’s nuclear programme.
Presidents Trump and Macron are expected to tackle pressing foreign policy issues from Iran deal to Syria as French leader starts US state visit.
French president has expressed his concern to Iranian president Hassan Rouhani over number of casualties in six days of protests.