Iran's Intelligence Ministry says it has arrested a Swedish national on espionage charges after having him under surveillance for a while.

An intelligence ministry statement on Saturday did not name the Swedish national or provide any information about his age or whereabouts, the Telegraph reports.

It also remains unclear whether this is the same individual whose arrest was announced by the Swedish Foreign Ministry in May.

At the time, Sweden said a tourist in his 30s had been arrested, but Iran had not reported the arrest.

But the Iranian intelligence ministry's statement on Saturday mentioned that the arrested individual's travels were closely monitored from the unspecified time he entered the country and that his travels were "completely outside tourist destinations and practices".

"Findings from the ministry's counter-espionage structure show that the Swedish suspect was in contact with a number of suspected European and non-European elements in Iran, using professional communication and security practices and secrecy," the statement said.

The ministry said the Swedish citizen re-entered the country several months ago, shortly after "another European spy" was arrested.

The individual's goal, he claimed, was to find out how the other person was arrested and what information they had, which led to the arrest of the Swedish national trying to leave the country.

Iran's intelligence ministry also said the arrested person had a history of traveling to Israel.