Iraq's disputed oil-rich Kirkuk province may turn into fertile ground for militant groups including Al-Qaeda after the US withdrawal, officials from the province warn.

Ethnically divided Kirkuk lies at the centre of a tract of territory which Kurdish leaders want to incorporate in their autonomous region in the north despite the opposition of many of the province's Arab and Turkmen residents, and of Iraqi Prime Minister Nuri al-Maliki.

"The US withdrawal and lack of readiness of the Iraqi security forces will be used by forces opposed to the political process, and in particular Al-Qaeda," Kirkuk provincial council member Sherzad Adel said.

Al-Qaeda "want to have a foothold in Kirkuk," he said, noting that "the conflict between the centre (Baghdad) and the region (Kurdistan), and the failure to resolve problems in Kirkuk are two factors that form fertile ground for terrorism."

US forces have played the role of mediators in Kirkuk, and were involved in setting up the "Golden Lions" unit made up of Arab and Kurdish forces.

But all US soldiers except for a small contingent under US embassy authority are to depart Iraq by the end of 2011 leaving a dangerous security vacuum, officials say.

"We have indications that Al-Qaeda is reorganising and coordinating with the other remaining armed groups to launch operations," said Major General Turhan Abdul Rahman, the deputy director general of the Kirkuk police and commander of its anti-terrorism force.

There are signs that operations are in preparation including kidnappings and bomb attacks, Abdul Rahman said.

"But we will stand strong to face them despite the challenges we face today, including the absence of US forces that provided us with aerial reconnaissance and surveillance."

Abdul Rahman expects Al-Qaeda and other militant groups to focus their activities on Kirkuk and other north Iraq cities "because they are trying to stir up nationalist strife."

General Lloyd Austin, the top US general in Iraq, on Monday also warned about the threat from Al-Qaeda, specifically in Iraq's north.

"We expect that Al-Qaeda will continue to do what it has done in the past," he said. "We expect that it's possible that they could even increase in their capability.

"Of course, that will depend on how effectively the Iraqi security forces and the government of Iraq are able to focus on that network."

Major General Jamal Taher, the director general of the Kirkuk police, said that his forces were ready to assume security responsibilities from US forces after the withdrawal from Iraq.

But Taher warned that "all components" of Kirkuk's ethnically fragmented society were "subject to terrorism."

Sectarian disputes over Kirkuk pose a threat to today's fragile status quo.

"Kirkuk may be one of the ticking bombs after the US withdrawal from Iraq, especially in the conflict between Arabs and Kurds," said Ihsan al-Shammari, a political science professor at Baghdad University.

The fate of a US military base in the region sparked a recent Arab-Kurd row, offering a glimpse of the potential for conflict in the province.

Kurdish politicians said that the base should be guarded by police, as the provincial council had voted to turn the base into a civilian airport, and condemned an Iraqi army handover ceremony held on the site.

The dispute was eventually resolved with an agreement for the army to guard the base for now, after the Iraqi premier said he was amenable to turning it into a civilian airport.

Sheikh Abdulrahman Munshid Aasim, one of the leaders of the Arab Political Council in Kirkuk, said he does not expect "the emergence of Al-Qaeda activity as we have known in 2006 and 2007."

Rather, the conflict will be "Arab-Kurd in areas of common interest, with Kirkuk at its heart, and this is more dangerous than Al-Qaeda's work."