"Seven people tied with counter-revolutionary and Zionist satellite networks and the sedition have been arrested," the intelligence ministry said in a statement carried by local media.
It said the detainees were linked to Radio Farda — the US-funded, Prague-based Persian radio — and trained in Dubai and Istanbul, while "some of them were hired by the US spy service," which was not named.
The accused had a crucial role in gathering and sending news abroad and "provoking rioters, especially on Ashura," the ministry charged.
"They were due to do the same on February 11 and then leave the country to join the Americans."
The scene of tense protests since June's disputed re-election of President Mahmoud Ahmadinejad, Iran saw the bloodiest unrest in recent months on December 27 when the nation was commemorating the solemn Shiite ceremony of Ashura.
Opposition supporters have staged anti-government protests to coincide with several regime-sponsored events, with expectations high of a repeat performance on February 11.
