Bahrain Mirror- AFP: Iraqi Defence Minister Khalid al-Obeidi accused the parliament speaker and several lawmakers of corruption and blackmail on Monday, prompting the prime minister to order an investigation.

The political row surrounding the defence minister comes as Iraq prepares for a drive to retake second city Mosul, the biggest operation yet in the country's war against the Islamic State jihadist group.

Obeidi made the accusations as he appeared in parliament for questioning over corruption allegations brought by Alia Nasayif, a lawmaker whom the defence minister asserted was herself corrupt.

The session broke down after Obeidi made the accusations, and parliament speaker Salim al-Juburi then held a press conference denying them.

Obeidi said that he was facing questioning as retribution for his rejection of corruption in connection with the supply of food for the military, saying that lawmaker Mohammed al-Karbouli was involved.

Karbouli also sought to inflate the price of armoured vehicles, Obeidi said.

And Obeidi said that a businessman had asked him in Juburi's presence to replace the head of the air force because he was "not cooperating with us."

The minister also accused Nasayif of requesting that the ministry illegally transfer ownership of 127 properties that had belonged to ousted dictator Saddam Hussein's regime.

And he said that a former lawmaker told him that "we will shut up MP Hanan al-Fatlawi in exchange for $2 million," referring to a member of parliament who has been critical of the minister.

Posts on Obeidi's official Facebook page generally outlined his accusations, including one that said he told parliament that Juburi was "involved in attempting to pass corrupt armament contracts".

Another charged that Juburi and three lawmakers had sought to blackmail the minister "for the purpose of passing corrupt deals and contracts at the expense of Iraqi blood".

- 'Theatre' -

Obeidi later took to Twitter to make similar points, saying he had revealed the "names of MPs and politicians who practise acts of blackmail against him to pass corrupt contracts, among them the (speaker) of parliament."

Prime Minister Haider al-Abadi responded by ordering Iraq's anti-corruption commission to investigate the allegations and to cooperate with a parliamentary investigative committee on the issue, his office said in a statement.

"No one is above the law," the statement said.

Following the session, Juburi held a news conference rejecting the accusations against him and the MPs.

"Everything that was raised today is theatre" aimed at allowing Obeidi to avoid questioning by parliament, Juburi said.

Corruption is widespread in Iraq's government, from senior officials to low-level functionaries, and while Iraqis have repeatedly demonstrated for change over the past year, little in the way of real reform has taken place.

The latest parliamentary acrimony follows weeks of deadlock in the legislature over Abadi's efforts to replace the cabinet earlier this year.

And it comes as Iraqi forces conduct operations to set the stage for an assault on Mosul, which has been held by IS jihadists since June 2014.

The conflict between Obeidi and Juburi -- two of the country's most senior Sunni Arab politicians -- does not bode well for unity in the community ahead of the battle to retake the Sunni-populated city.