MOSCOW (Reuters) - Russian President Vladimir Putin said on Wednesday that the U.S. administration was taking "vigorous steps" to try to secure the release of detained Wall Street Journal reporter but said such questions could only be resolved on the basis of reciprocity.

Putin said talks with U.S. intelligence agencies on the subject were ongoing, but needed to be conducted in private.

Gershkovich became the first U.S. journalist arrested on spying charges in Russia since the Cold War when he was detained by the Federal Security Service (FSB) in March 2023.

He and his newspaper deny the accusations against him.

"You know, you believe that he is not guilty of anything," Putin told a foreign reporter who asked him a question about Gershkovich.

"And Russian law enforcement agencies and special services believe that he has committed actions, illegal actions, which are called espionage."

(Reporting by Reuters; Writing by Maxim Rodionov; Editing by Andrew Osborn)