TEHRAN, Feb. 9 (UPI) -- A national poll in Iran is a legal way to determine how the public views the important issues of the day, said opposition leader Mehdi Karroubi.

Karroubi, who waged an unsuccessful challenge to President Mahmoud Ahmadinejad in June elections, called for a national poll to "to discover the opinion of the populace regarding some of the important issues of national concern," reports Radio Zamaneh, an Amsterdam-based Persian news agency.

Karroubi through his reformist Etemad-e Melli political party said he was advocating the poll because Tehran had strayed from the principles of the Islamic Revolution.

"Using religion as a tool, discrimination and inequality amongst ethnicities and religions, indifference of the authorities to the will of the people and using violence in resolving debates" were among his litany of complaints.

His statements come as Tehran prepares for celebrations Thursday marking the 31st anniversary of the success of the Islamic Revolution.

Supporters of Grand Ayatollah Ruhollah Khomeini overwhelmed forces loyal to Shah Mohammad Reza Pahlavi on Feb. 11, 1979.

Supporters of the opposition Green Movement in Iran are expected to wage mass demonstrations on Thursday in protest of the government. Demonstrations on the holy day of Ashura in December turned violent, leaving as many as eight dead.

Opposition leaders called on their supporters to avoid violence during protests planned for Thursday.

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