Mehdi Karroubi
Mehdi KarroubiReuters

A leading member of the Iranian opposition who has been under house arrest for almost six years announced on Tuesday he is quitting his party, AFP reported, citing Iranian media.

“Considering my situation since (2011) and given that I do not know how long this will last, I ask my friends to accept my resignation,” Mehdi Karroubi, 79, wrote in a letter to his party.

Karroubi and Mir Hossein Mousavi were reformist candidates during the 2009 presidential election, and questioned the shock victory of Mahmoud Ahmadinejad which led to mass protests.

A year later, in 2010, government forces firebombed the five-story Tehran home of Karroubi, and beat his bodyguard into unconsciousness.

In 2011, both leaders ended up under house arrest for their part in the protests, which regime leaders call “the sedition”.

There have been repeated calls for Karroubi and Mousavi to be tried in court to no avail, noted AFP.

Ahmadinejad’s successor Hassan Rouhani, despite being touted by the West as a “moderate”, did not act to release the two from house arrest despite promising to do so during the 2013 election campaign.

Hardliners claim house arrest was actually an “act of clemency” for the two leaders, since otherwise they would be put to death for sedition.

Sadegh Larijani, the head of the judiciary, which is considered close to hardliners, said Monday that the “sedition dossier is still open and will be examined,” without giving further details.

Karroubi said his resignation was aimed at preserving the unity of his party, National Trust, ahead of the presidential election in May – despite it being banned since his arrest.

“While keeping its independence, the party must cooperate with the other reformist groups and movements,” he wrote, according to AFP.