"That will have to obviously be something that the Iraqi government will need to agree to and I think there's agreement there in principle," US Secretary of Defense Ash Carter told reporters. "But now we're down to the practicalities of that ... and that's what we're working through."
Carter was in Ankara on Friday to meet with Turkish President Recep Tayyip Erdogan.
Turkey’s assistance could also be non-military, Rudaw reported.
Turkey has a training base and heavy weapons in Iraq’s Bashiqa region, where it has been training the 3,000-strong Nineveh Guard militia which it wants to participate in the Mosul operation. To date none of these forces have fought in the operation, which began on Monday, and Turkish jets have not carried out any airstrikes on Daesh (ISIL) targets in Mosul.
The Turkish government justifies its deployment at Bashiqa as a necessary security precaution and also insists that the Nineveh Guard should participate in the Mosul operation to avoid sparking any sectarian hostilities. Iraq has said it will not permit Hashd al-Shaabi forces to participate in operations inside that Sunni-majority city to minimize the prospect of such hostilities.
Baghdad considers Turkey’s presence on its soil a violation of sovereignty and has appealed to the United Nations to compel Turkey to withdraw from Iraq.
Turkey’s Defense Minister Fikri Isik, after meeting with Carter, pledged to “work jointly on Turkey’s participation in the Mosul campaign and on Turkey being at the table in the process after that.”
He confirmed that an agreement had been reached in principle.