TEHRAN, June 20 (Xinhua) -- Iran's former Prime Minister, defeated presidential candidate Mir-Hossein Mousavi renewed his call on Saturday for cancellation of last week's disputed presidential election.

    In a letter to Iran's Guardian Council which was published on his campaign website, Mousavi cited "irregularities in election" as the reason for a nationwide cancellation of the election result.

    Mousavi said in the letter that the wise Iranian nation would never believe the inequity and irregularity in the election.

Iran's presidential election candidate Mirhossein Mousavi speaks during a news conference in Tehran June 12, 2009

    "I will continue my steps to make the truth and the rights of the great Iranian people clear in the range of Constitution and current laws," Mousavi said.

    Mousavi cited several allegations of irregularities in the election which gave incumbent President Mahmoud Ahmadinejad a landslide victory, saying that they were "part of the truth and fraudulent conduct."

    "Irregularities had began some month ago," Mousavi added.

    Iran's Supreme Leader Ayatollah Ali Khamenei said on Friday that the Iranian nation needs calm and patience, rejecting any vote rigging in the recent presidential election.

    Khamenei also urged the candidates to lodge any complaints about the election through legal channels.

    On June 13, Iran's Interior Minister Sadeq Mahsouli said Ahmadinejad won 62.63 percent of the total ballots on the June 12 presidential vote, while his main rival Mousavi got 33.75 percent.

    After the official declaration, Mousavi protested "strongly" the "obvious" violations in Iran's presidential election, and also appealed to the Guardian Council for a cancellation of the election result.

    Mousavi's supporters have participated in massive rallies in Tehran and other cities over the past days.