Karrubi, a 68-year-old, mid-ranking cleric, stood as a candidate in the last parliamentary elections but failed to win a seat.
The Guardians Council has also approved the candidacy of powerful former President Ali Akbar Hashemi-Rafsanjani, a pragmatic conservative who is considered the likely front-runner.
Ali Larijani, the former head of broadcasting and a close adviser to Iran’s supreme leader, is also approved to run, as is Tehran Mayor Mahmoud Ahmadinejad.
The conservative Guardians Council has also cleared two candidates with military background: former police chief Mohammad Baqer Qalibaf and former Revolutionary Guard chief Mohsen Rezayi.
But the main candidate of Iran’s main pro-reform party, Mostafa Moin, and the head of the banned Freedom Movement party, Ibrahim Yazdi, are disqualified. So are an adviser to current moderate President Mohammad Khatami and several women.
Iran’s reformist camp has expressed shock and anger at the disqualification of Moin, and a top reformist has called it “a coup d’etat.”
Moin himself has described the decision to bar him as "illegal, unfair, and illogical.” He said he will protest the disqualification.
The main reformist party -- the Islamic Participation Front (Mosharekat) -- is quoted as saying, "Moin is the party’s red line (non-negotiable demand) and our only condition for participating in the election.”
However, no final decision on a possible boycott has been made. Mohsen Armin, a former reformist lawmaker, has said that decisions regarding the elections will be made after a meeting that is due to be held in support of Moin on 26 May.
Mohammad Sadegh Javadi Hessar, a pro-reform journalist in the northeastern city of Mashad, said he thought it is unlikely that the reformists will actually boycott the elections.
“It is predicted that if they stand on their current positions, the least is that they will not present a candidate and they will not make a call for people’s participation on a large scale," Javadi Hessar said. "But at the same time, the predictions are that they will not boycott the elections but they will say that whoever feels that his vote has an effect can vote.
The Guardians Council
The Guardians Council, an unelected body that includes six theologians and six jurists, screens candidates according to their religious credentials and faithfulness to the Islamic establishment.
Reformists have accused the Guardians Council in the past of being politically biased toward the conservatives.
Iran’s former vice president, Mohammad Ali Abtahi, said the current disqualifications "show that there is a plan to help one particular ideology rule the country."
Moin has criticized pressure on Iran’s student movement and the jailing of student activists. He resigned from President Hojatoleslam Mohammad Khatami’s cabinet in 2003 after a bill that he put forward to restructure Iran’s education system was rejected by the Guardians Council. He had promised to tackle human rights abuses if elected.
Dr. Sadegh Zibakalam is a professor of political science at Tehran’s university, said he thought Moin was probably disqualified because of his views.
“The Guardians Council has not disqualified Moin because of fear that he would gain votes and become the next president; it was not like that, because all the opinion polls showed that Moin would gain some 5 percent of the vote. The reasoning of the Guardians Council for disqualifying Moin is probably that Moin had radical positions; he had criticized a lot, talked a lot.”
Zibakalam said the Guardians Council decision to bar Moin from running will severely damage Iran’s international image.
During Iran’s last parliamentary elections in February 2004, Tehran came under international criticism after the Guardians Council disqualified more than 2,000 pro-reform and independent candidates.
The Guardians Council’s right to veto candidates is seen by many as one of the main obstacles to free elections in the Islamic Republic.
Abdolkarim Lahidji, the vice president of the International Federation of Human Rights in Paris, predicted that the upcoming presidential election in Iran will be neither free nore competitive.
“We’ve seen many times in Iran -- during presidential or parliamentary elections – that the Guardians Council give itself the right to disqualify hundreds of candidates without even justifying itself and giving an explanation and publishes a limited list," Lahidji said. "Therefore we are facing an election that has two degrees: first, the Guardians Council does whatever it wants; secondly, the election is not public because a big part of people cannot stand as candidates and it’s not free. In general, unfortunately, none of the conditions stated in the Article 21 of the [UN’s] Universal Declaration of Human Rights about elections is being respected in these elections.”
Lahidji said he belives the turnout in the June election will be lower than the turnout in the 2004 parliamentary elections, where some 50 percent of eligible Iranians voted.
Last week, some 500 politicians, intellectuals, and student activists announced in a statement that they will not take part in the presidential election because the Guardians Council is depriving Iranian citizens of free choice.
They said that to participate massively in an election that will not bring democracy will only serve to give the regime a semblance of legitimacy.
The 17 June election is to replace President Khatami, who according to Iran’s constitution cannot seek a third term.
(Radio Farda correspondent Shirin Famili contributed to this report.)