Iran has detained a Franco-German national on a Europe-to-Asia cycling trip who disappeared in the country, Iranian Foreign Minister Abbas Araghchi told a French newspaper on Thursday.
"He was arrested for committing an offence, and an official notification regarding his situation was sent to the French embassy," Araghchi told French daily newspaper Le Monde, without providing further details.
France's foreign ministry said it was in contact with Iranian authorities and the family of Lennart Monterlos, who went missing on June 16. The French ministry said it would give no further comment, as his safety was at stake.
The arrest is likely to worsen already strained ties between Paris and Tehran.
Iran has already been holding two other French citizens, Jacques Paris and Cécile Kohler, for more than three years in conditions France has said are akin to torture.
Read moreIran charges French detainees Cécile Kohler and Jacques Paris with spying for Israel
France has called their detention state-sponsored hostage taking and demanded they be released immediately.
France and a number of other countries have urged their nationals not to go to Iran because of the risk of detention.
French detainees moved from Evin prison in June
Earlier on Thursday, France's foreign ministry spokesperson Christophe Lemoine said Paris was trying to get permission to visit the French nationals detained in Iran.
Paris and Kohler were moved from Tehran's notorious Evin prison following airstrikes by Israel that targeted the prison in June. French consular officials visited them at a new location on July 1, but no longer knew where they were being held now, he said.
Iran in June charged the two with spying for Israel's Mossad intelligence service.
Iran's Revolutionary Guards have detained dozens of foreign and dual nationals in recent years, often on espionage-related charges. Rights groups and Western countries accuse Tehran of using foreign detainees as bargaining chips, which it denies.
France filed a case in May at the World Court against Iran for violating the right to consular protection, in a bid to pressure Tehran over the detention of its two citizens.
(FRANCE 24 with AFP and Reuters)