Iraqi Prime Minister Haider al-Abadi has been forced to deny that he struck up a deal with the US to keep American troops in the country after the defeat of Isis.

It follows an Associated Press report which said US Defense Secretary James Mattis was in talks with Abadi to maintain a "modest" presence of troops in Iraq.

Mattis said the number of troops would be "several thousand… similar to what we have now, maybe a little more". However, Abadi released a statement emphasising that only so-called "military advisors" would remain.

"The Iraqi government did not agree with any state in the process of their military role with Iraq after its decisive victory over terrorism," he said.

"The Iraqi government has plans and strategies to develop the capabilities of our security forces through training and arming to raise their readiness to face the challenges ahead.

"It is open to all international expertise to meets the aspirations of Iraq to build military institutions and security apparatuses that enjoy full readiness to face any future security challenges, whether external or internal and in accordance with the requirements of Iraqi national sovereignty."

The Pentagon currently has close to 7,000 US soldiers in Iraq.

Troop levels reached as many as 170,000 in 2007, during the height of the post-war insurgency, but were wound down to 40,000 before a full withdrawal in 2011.

At the invitation of the Iraqi government, former President Barack Obama recommitted troops to Iraq in 2014.

Currently, US soldiers are backing Iraq's army in a major offensive to drive Isis out of Mosul, but the war against the terror group is expected to continue into other parts of the country once that objective is complete.

Haider al-Abadi
File picture of Iraqi Prime Minister Haider al-Abadi, Reuters