The French government announced it had frozen assets belonging to two Iranians and Iran's ministry of security and intelligence following the alleged plot to bomb an Iranian opposition group in a Parisian suburb in June.
"This extremely serious act envisaged on our territory could not go without a response," France's interior, foreign and economy ministers said in a rare joint statement.
"In taking this decision, France underlines its determination to fight against terrorism in all its forms, particularly on its own territory," they added.
The foiled attack in June was to have targeted a meeting of thousands of Iranian opposition supporters which was also attended by leading US figures, including close allies of President Donald Trump.
Six people were arrested afterwards in coordinated raids by European police forces, including an Iranian diplomat called Assadollah Asadi, who is set to be extradited from Germany to Belgium for prosecution.
Asadi was targeted by France for the six-month asset freeze on Tuesday along with another man named as Saeid Hashemi Moghadam.
Iran has denied any involvement in the alleged bomb plot and said the opposition group, the People's Mujahedeen of Iran (MEK), had orchestrated the plot to discredit Iranian President Hassan Rouhani as he embarked on a tour of Europe.
The counter measures by France could have major diplomatic repercussions at a time when France is working to keep Iran in the 2015 accord to limit its nuclear programme amid major tensions in the Middle East.
French President Emmanuel Macron had vowed to visit Tehran early in his term as president, but major differences between the countries on issues such as the wars in Syria and Yemen, as well as the bomb plot, have led to tensions.
- Raids on Islamic centre -
Also Tuesday, around 200 police launched a dawn anti-terror raid on one of the biggest Shiite Muslim centres in France, the Zahra Centre France, as well as the homes of its directors.
A total of 11 people were questioned and three were arrested, security sources told AFP, including for the illegal possession of firearms.
The Zahra Centre France was founded in 2009 by Yahia Gouasmi, who has spoken in support of Lebanese Islamist group Hezbollah and the Iranian supreme leader Ayatollah Ali Khamenei.
Gouasmi is also the founder of the Anti-Zionist Party in France and is an associate of controversial comedian Dieudonne M'bala M'bala, a convicted anti-Semite.
The raids on Tuesday were staged as part of the "prevention of terrorism" procedures, regional authorities said in a statement.
Police have been closely following the activities of the Zahra Centre "because of the strong support by its leaders for several terrorist organisations and in favour of movements backing ideas that are contrary to the values" of France, a statement from local authorities said.
On its website, the association says its purpose since its foundation in 2009 has been "to make known the message of Islam through the eyes of the Prophet and his family."
