TEHRAN, (Reuters) – A man arrested on suspicion of leaking secrets of Iran’s disputed nuclear activities to an exiled opposition group has been sentenced to three years in jail, the semi-official Fars news agency said on Saturday.

Fars said the lower court had also fined the man, who it said worked in the parliament’s research centre but did not name, 25 million rials ($2,720).

It quoted an “informed source” as saying the sentence had been appealed. Judiciary officials were not immediately available for comment.

State radio said in January the man was arrested on suspicion he handed over classified information on Iran’s nuclear activities to the People’s Mujahideen.

The People’s Mujahideen, labelled a terrorist group in the European Union and the United States, exposed Iran’s covert nuclear programme in 2002.

The group lacks support in Iran where few can forgive it for siding with Saddam Hussein in the 1980-88 Iran-Iraq war.

The West suspects Iran is seeking to develop nuclear weapons but Tehran says it is only building a civilian nuclear industry in order to generate electricity so that it can export more of its valuable gas and oil.

Earlier this week, official media said Iranian authorities has arrested a former Iranian diplomat “for security reasons”.

Hossein Mousavian, considered a moderate conservative by analysts, was a member of Iran’s nuclear negotiating team with the European Union and head of the foreign policy committee on the Supreme National Security Council.

But like most other members of the team, he was replaced by more hardline officials when President Mahmoud Ahmadinejad took office in 2005.