BAGHDAD: Iraqi Vice President Iyad Allawi warned Monday there could be a “civil war” over the Kurdish-administered city of Kirkuk if talks over Kurdish independence are left unresolved.

Iraq’s central government meanwhile unleashed a legal barrage against Kurdish officials and sought to seize key businesses in a fresh bid to tighten the screws over the disputed independence referendum.

Allawi, in an interview with the Associated Press, urged Kurdish leader Massoud Barzani, as well as Iraq’s central government and its Iranian-backed militia forces, to show restraint and resolve their disputes over the oil-rich city.

The head of the Asaib Ahl al-Haq militia Qais Khazali warned worshippers in a sermon Sunday that Iraq’s Kurds were planning to claim much of north Iraq, including Kirkuk, for an independent state, after Iraq’s Kurds voted for independence in a controversial but non-binding referendum two weeks ago.

He said it would be tantamount to a “foreign occupation,” according to remarks reported by the Afaq TV channel, which is close to the state-sanctioned militia.

Allawi, a former prime minister, said any move by the country’s Al-Hashd al-Shaabi militias, which include the Asaib Ahl al-Haq, to enter Kirkuk would “damage all possibilities for unifying Iraq” and open the door to “violent conflict.”

“The government claims they control the Al-Hashd al-Shaabi forces. If they do they should restrain them, rather than go into a kind of civil war. And there should be a restraint on Massoud Barzani and the peshmerga not to take aggressive measures to control these lands,” Allawi said.

Kirkuk was included in the September referendum even though it falls outside the autonomous Kurdish region in the northeast Iraq. The ethnically mixed city has been administered by Kurdish forces since 2014, when government forces fled from the advancing Daesh (ISIS).

Also Monday, in a new round of attempts to ratchet up pressure, Baghdad’s National Security Council announced that a probe has been launched into Kurdistan’s lucrative oil revenues and officials in the region who might have illegally monopolized the market.

“The corrupt will be exposed and the funds recovered,” said a statement from the council, headed by Prime Minister Haider al-Abadi.

The council also said that “a list of names” of Kurdish officials who helped organize the referendum had been compiled and “judicial measures have been taken against them,” without giving more details.

The central government also demanded Kurdish-based cellular network operators relocate their headquarters to Baghdad Monday. Two of Iraq’s three main network operators are headquartered in the Kurdish region, namely Asiacell and Korek Telecom.

Abadi’s Cabinet asked Turkey and Iran to close their crossings with the Kurdish region and liaise exclusively with Baghdad. The Kurdish region is responsible for up to a quarter of Iraq’s oil production, with a portion of it exported directly to Turkey.

The prime minister has demanded the Kurdish peshmerga forces accept joint administration over Kirkuk.

Turkey and Iran also threatened punitive measures against the region, fearing Kurds in their own countries would renew their campaigns for self-rule.

But they also see an opportunity to expand their influence in fragile north Iraq, which is reeling from the war on Daesh. The fight has drawn the Shiite-dominated Popular Mobilization Front militias deep into Sunni-majority northern Iraq.

Shiite politicians close to Iran are urging a hard line against the Kurdish regional government in response to the referendum. They seek to curb Kurdish ambitions, which they see as the biggest obstacle to expanded Iranian influence in north Iraq.

Allawi, also a Shiite but one of Iran’s detractors in Baghdad, warned against opening the door to foreign interference.

“Kirkuk has become a flashpoint,” Allawi said. “Iraqis should be left alone to discuss their own problems.”

Barzani has not declared independence for any part of northern Iraq.