A woman walks past posters with the portraits of Cecile Kohler and Jacques Paris, two French citizens held in Iran, on the day of support rallies to mark their three-year detention and to demand their release, in front of the National Assembly in Paris, France, May 7, 2025. The slogan reads “Freedom for Cecile Kohler and Jacques Paris.” Photo: REUTERS/Abdul Saboor

France will file a case at the World Court on Friday against Iran for violating the right to consular protection, foreign ministry spokesman Christophe Lemoine said on Thursday, a bid to pressure Iran over the detention of two French citizens.

Paris has toughened its language towards Iran in recent months, notably over the advancement of Tehran’s nuclear program and its military support for Russia, but also over the detention of European citizens in the country.

Cecile Kohler and her partner Jacques Paris have been held in Iran for more than three years. France has repeatedly accused Iran of holding them arbitrarily, keeping them in conditions akin to torture in Tehran’s Evin prison and not allowing proper consular protection.

Iranian officials deny these accusations.

“France will maintain pressure on the Iranian authorities until our two compatriots are freed. Their liberation is a national priority,” Lemoine told a news conference.

He said French officials would file the case on Friday at the International Court of Justice (ICJ), which is based in The Hague, for violating the 1963 Vienna Convention on Consular Relations.

Like France, Iran is party to the convention, which defines the framework for consular relations between states, including guaranteeing their right to provide proper consular protection to their citizens.

Cases at the ICJ, also known as the World Court, take years to come to a final ruling. Parties can request the court to order emergency measures to ensure that the dispute not deteriorate while the case is making its way through the United Nations’ top court.

In recent years, Iran‘s elite Revolutionary Guards have arrested dozens of dual nationals and foreigners, mostly on charges related to espionage and security.

Rights groups have accused Iran of trying to extract concessions from other countries through such arrests.

Iran denies taking prisoners to gain diplomatic leverage.