Iran accused France on Sunday of "interference" in the case of an Iranian-French academic held in the Islamic republic, saying she is considered an Iranian national and faces security charges.
France said Friday it summoned Iran's ambassador to protest the imprisonment of Fariba Adelkhah and another academic, Roland Marchal of France, saying their detention was "intolerable".
Their imprisonment has added to distrust between Tehran and Paris at a time when French President Emmanuel Macron is seeking to play a leading role in defusing tensions between Iran and its arch-foe the United States.
"The statement by France's foreign ministry regarding an Iranian national is an act of interference and we see their request to have no legal basis," Iran's foreign ministry spokesman Abbas Mousavi said in a statement.
"The individual in question (Adelkhah) is an Iranian national and has been arrested over 'acts of espionage'," he said, adding that her lawyer had knowledge about the details of the case which is being investigated.
Iran does not recognise dual nationality and has repeatedly rebuffed calls from foreign governments for consular access to those it has detained during legal proceedings.
In its statement on Friday, the French foreign ministry reiterated its call for the release of Adelkhah and Marshal.
It also reaffirmed France's demand for consular access.
In response, Mousavi said Marshal was detained for "conspiring against national security", that he has had "consular access multiple times" and that his lawyer was in touch with the judiciary.