Updated

Iran's parliament is set to summon President Mahmoud Ahmadinejad for questioning over an economic scandal and his polices after the required number of lawmakers signed a petition Sunday, the latest salvo in a long battle between the president and his rivals.

Ahmadinejad would be the first president to be hauled before the Iranian parliament, a serious blow to his standing in a the conflict involving the president, lawmakers and Iran's powerful clerics.

At least 73 lawmakers signed the petition to question Ahmadinejad, just above one-quarter of the 290 members required by Iran's constitution to call in a president.

Earlier the parliament found Ahmadinejad's economics minister guilty in relation to a $2.6 million fraud case, considered the largest in Iran's history.

This is just one of several economic misconduct cases that target Ahmadinejad allies, evidence that his political struggles are a factor. Ahmadinejad has been wrestling with the parliament and the clergy over in the run-up to parliamentary elections in March and a presidential election in 2013.

Ahmadinejad has come under increasing attacks in recent months from the same hard-liners who brought him to power.

Dozens of Ahmadinejad's political backers have been arrested or hounded out of the public eye by hard-line forces in recent months. His protege and top aide, Esfandiar Rahim Mashaei, has been effectively blackballed from his goal of succeeding Ahmadinejad in 2013 elections by a series of reputation-killing accusations.

They include leading a "deviant current" that seeks to challenge the system of theocratic rule, and alleged links to the $2.6 billion bank fraud.

The questioning, should it happen, would be a serious blow to Ahmadinejad, who has already been weakened after he publicly challenged Khamenei in April over the choice of intelligence minister.

The $2.6 billion fraud case involving top government officials has reinvigorated efforts by lawmakers to seriously bring Ahmadinejad before the house.

"The petition to question the president has reached the minimum of signatures required. It was handed over to the presiding council," lawmaker Hossein Sobhaninia said.

The parliament's presiding council acknowledged receiving the petition Sunday, clearing the way to bring the president before the house.

At a session of parliament broadcast live on state radio Sunday, a report was read saying that a parliamentary investigation has found top government officials guilty in the case, described as the nation's biggest financial scam.

Economy Minister Shamsoddin Hosseini is set to be impeached Tuesday over the case.

Sobhaninia, a member of the presiding council, said a special parliamentary committee will question a representative of the president before Ahmadinejad himself is summoned before the house.

Dozens of Iranian lawmakers signed a similar petition last year, but later, several lawmakers withdrew their signatures, killing the move.

Ali Motahari, a conservative lawmaker behind the petition, resigned earlier this month to protest the parliament's failure to summon Ahmadinejad for questioning. He charged that he could no longer protect the rights of the people who elected him to parliament.

On Sunday, Motahari said he will withdraw his resignation if the president is actually questioned.

The $2.6 billion fraud case involved the use of forged documents to obtain credit from at least two Iranian state banks to purchase state-owned companies.

Iranian businessman Mahafarid Amir Khosravi, also known as Amir Mansour Aria, has been accused of masterminding the scam, a scandal that broke in September.

A long report on parliament's investigation found Hosseini, the economy minister, his deputies and managers of the Central Bank of Iran as well as managers of the banks involved in the fraud case guilty of failing to take action despite having knowledge of the offenses.