Iraqi federal police take up positions in Rashad, southern Kirkuk, on Oct. 13. According to news reports, Iraqi forces launched an operation to capture the disputed city of Kirkuk and seize Kurdish peshmerga positions. (Lateef/Epa-Efe/Rex/Shutterstock)

Iraqi forces have demanded that Kurdish troops withdraw from oil fields and military bases around the contested city of Kirkuk, Kurdish officials and a senior militia leader said Friday, leading to a tense standoff around the city.

Kurdish peshmerga soldiers rallied to protect Kirkuk on Thursday night, as Interior Ministry troops and Shiite militias mobilized nearby. Volunteer and retired fighters bolstered the lines. Several positions were taken over by Iraqi forces, however, with Kurdish officers saying they received orders to withdraw.

The Kirkuk area, with about 10 percent of Iraq's oil reserves, has long been contested by the central government in Baghdad and Kurdish authorities in Irbil, but the province has become even more of a flash point since the Kurdistan region voted in favor of independence in a referendum last month.

[Kurdish bid for independence from Iraq emerges as regional flash point]

At the center of the military conflagration are areas that forces loyal to Baghdad occupied before the Islamic State's advance in 2014 but lost as Iraqi forces collapsed en masse in northern Iraq.

Kurdistan sees Kirkuk — ethnically and religiously mixed and home to Kurds, Arabs, Turkmens, Assyrian Christians, Sunnis and Shiites — as a historically Kurdish city where demographics were shifted by a campaign of "Arabization" under Iraq's former dictatorial ruler, Saddam Hussein. Baghdad contests that claim.

Relations between Baghdad and Irbil have deteriorated in recent weeks after the semiautonomous government in the north defied the vehement opposition of Baghdad, as well as that of the United States and Kurdistan's neighbors, to hold the independence vote. Baghdad has blocked international flights to Irbil in retaliation and has threatened to take over border crossings.

[Iran blocks flights to Iraq’s Kurdish region ahead of independence vote]

"I call on our brothers of the peshmerga to hand over these ­areas and not to drag the country into internal war," said the militia commander, Hadi al-Amiri, head of the Iran-backed Badr Organization. He said Iraq is demanding that oil fields and military bases be handed over.

In Baghdad, Iraqi Prime Minister Haider al-Abadi took to Twitter on Friday to dismiss reports that Iraqi forces were planning to attack Kurdistan as "fake news" with a "deplorable agenda." Other commanders said Iraqi forces' movements were related to securing the nearby town of Hawijah, which was recently recaptured from Islamic State militants.

But the country's interior minister, Qasim al-Araji, said that there was a "process of redeployment" underway that would see Iraqi forces return to the positions they held in the area before the Islamic State's advance in 2014, when the Iraqi army collapsed in huge areas of the country's north.

Najmaldin Karim, governor of Kirkuk province, said Baghdad demanded that the peshmerga retreat from the K-1 military base and the oil fields run by Iraq's North Oil Co. "They gave us an ultimatum," he said. "There were troop movements of Shiite militias. Some of them were disguised as the federal police; they were with elements of the army. They moved toward our vital infrastructure, power plants, gas and oil fields."

Kimberly Kagan, president of the Institute for the Study of War, said Araji's statement could be viewed by Kurdish authorities as a "statement of intent" designed to signal allied Shiite militias that they should proceed with a military buildup to reclaim lands once held by Iraqi forces. "I think the Kurds are reading the tea leaves correctly," Kagan said.

The fact that the demands were outlined by militia leaders and the Interior Ministry — which is run by the Badr Organization, one of Iraq's most powerful militias — raised questions about the extent to which they were operating under the control of the central government.

Irsan Shukur, a member of the local council in Taza, south of Kirkuk city, said the council mediated between peshmerga, federal police and Iraqi Emergency Response Division troops when they moved into the area Thursday night. Peshmerga commanders agreed to retreat and left "without firing any bullets," he said, with the Iraqi troops arguing that they needed to take control to secure Hawijah, recently recaptured from the Islamic State.

"Two regiments refused to retreat, and currently we are negotiating with them to retreat," Shukur said. "The good thing is that all the sides agreed that it's not necessary to use violence."

Karim, the governor, denied that any peshmerga had retreated but said there had been natural redeployments because of the changing security situation.

One peshmerga officer in southwest Kirkuk said his unit withdrew Thursday night to another bank of a local river. He said he had received orders to withdraw but did not know why.

The unit was with the Patriotic Union of Kurdistan political faction, rather than the ruling Kurdistan Democratic Party. The PUK has been calling for dialogue with Baghdad.

"Not all the Kurds are the same," said the Badr Organization's Amiri. "There are those that are cooperating and those who are refusing to retreat and want war."

Footage shared on social media by members of the Emergency Response Division showed fighters pulling down a Kurdish flag from one peshmerga position near the city.

Kurdistan's prime minister, Nechirvan Barzani, called on the international community and Iraq's top Shiite cleric, Grand Ayatollah Ali Sistani, to intervene and support the peshmerga to prevent the city from becoming "another Mosul."

"We are surprised by the position of the Iraqi army," he said. "Everyone remembers how the Iraqi army fled from Kirkuk and the cities around."

Aaso Ameen Schwan in Irbil and Tamer El-Ghobashy in Cairo contributed to this report.

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