Laurent Vinatier was arrested in Moscow in June on charges of unlawfully collecting military information.
Moscow’s Zamoskvoretsky District Court ordered Laurent Vinatier to remain in custody until September on Wednesday.
The French national is set to go to trial on charges of unlawfully collecting information on military issues.
Russian authorities accused Vinatier of failing to register as a “foreign agent” while collecting information about Russia’s “military and military-technical activities” that could be used to harm the country’s security.
If found guilty, Vinatier could face up to five years in prison.
Vinatier was arrested in the Russian capital in June as tensions flared between Moscow and Paris after French President Emmanuel Macron’s raised the possibility of deploying French troops in Ukraine.
His plea to be released on bail or placed under house arrest was rejected.
Vinatier is an adviser with the Centre for Humanitarian Dialogue, a Geneva-based nongovernmental organization. The NGO said in June it was doing “everything possible to assist” him.
The NGO, which works to prevent and resolve armed conflict, commented that its activities are “impartial and independent”.
The charges against Vinatier stem from a recently adopted law that requires anyone who collects information on military issues to register with authorities as a foreign agent.
The law has been criticised by human rights activists who claim it is part of a multi-level approach for the Kremlin to crack down on independent media and political activists who are critical of Russia’s war in Ukraine.
Arrests on charges of spying and collecting sensitive data have become increasingly frequent in Russia since its full-scale invasion of Ukraine in February 2022.