Turkey, Iran and Iraq have agreed to consider counter-measures against Kurdish northern Iraq over a planned independence referendum, Turkey's foreign ministry said on Thursday.

In a joint statement, the foreign ministers of the three countries voiced concerns that the referendum would endanger the gains Iraq has made against Islamic State, and reiterated their fears over the potential for new conflicts in the region.

"In the meeting, the three ministers emphasised that the referendum will not be beneficial for the Kurds and the Kurdish Regional Government (KRG), and agreed, in this regard, to consider taking counter-measures in coordination," the statement said.

The statement gave no details on the possible measures but said the ministers, who were in New York attending the United Nations General Assembly, called on the international community to intervene.

Turkey's President Tayyip Erdogan has threatened to impose sanctions against Kurdish northern Iraq. Turkish troops are also carrying out military exercises near the border.

The central government in Baghdad, Iraq's neighbours and Western powers fear the vote could divide the country and spark a wider regional conflict, after Arabs and Kurds cooperated to dislodge Isis from its stronghold in Mosul.

The statement said Turkish Foreign Minister Mevlut Cavusoglu, Iranian Foreign Minister Javad Zarif and their Iraqi counterpart Ibrahim al-Jaafari expressed concerns that conflicts surfacing as a result of the referendum would "prove difficult to contain".

But the Kurds say they are determined to go ahead with the vote, which, though non-binding, could trigger the process of separation in a country already divided along sectarian and ethnic lines.

The three ministers also voiced their "strong commitment" to maintain Iraq's territorial and political unity, the foreign ministry's statement said.

Turkey, which has pulled forward a cabinet meeting and national security council session to Friday over the referendum, will also convene parliament for an extraordinary meeting on Saturday, the chairman of the ruling AK Party's parliamentary group said on Thursday.