"Iran will give its assistance to establish complete security in Iraq because Iraq's security is Iran's security," Iranian President Mahmoud Ahmadinejad told reporters after talks with Maliki in Tehran.

"We had a good discussion with Mr Ahmadinejad. Even in security issues there is no barrier in the way of cooperation," the Iraqi prime minister said for his part.

The Islamic republic has emerged as one of the strongest allies of the Shia-dominated government in Baghdad after the fall of Saddam Hussein, but has also drawn criticism for allegedly aiding Shia militants.

The US military in August accused Iranian forces of training and providing weapons to "Shia extremists" in Iraq in order to carry out violent attacks in the war-torn country.