Iran's parliament has summoned President Mahmoud Ahmadinejad to face questioning over the biggest banking fraud in the country's history.

The parliament announced on Sunday that it had found Ahmadinejad's finance minister guilty in relation to the $2.6bn fraud case involving top government officials.

The announcement came after at least 73 parliament members signed a petition calling for Ahmadinejad to be questioned in the latest economic misconduct case targeting an ally of the president.

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

Ahmadinejad is expected to appear before the assembly within the next 10 days, marking the first time the president would have to face direct questioning by politicians.

Forged documents

The 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, news of which broke in September.

Ahmadinejad has been wrestling with the parliament and the country's religious leaders in the run-up to parliamentary elections in March and a presidential election in 2013.

He has come under increasing attacks in recent months from the same people who brought him to power and dozens of his political backers have been arrested or hounded out of the public eye in recent months.

However, Foad Izadi, a professor of political communication at Tehran University, said the latest case does not represent a major embarrassment for Ahmadinejad.

"From the beginning, he has said he is going to fully co-operate with the judicial system to address the problem," Izadi told Al Jazeera.

"None of the people who are actually his opponents are implicating him in this scandal. His name is cleared, more or less.

"It's a question of neglect, not a question of being involved in the scandal. The question that the parliament has is, 'Why didn't you do your job properly in terms of watching the banking system?'"