Iraqi Kurdish forces deployed at a state-run oil company Thursday, temporarily halting pumping through a pipeline that is one of the country's two main avenues for crude exports, officials said.
The move highlights two fault lines that may increasingly come to the fore as Iraq's war against jihadists winds down: the dispute between Baghdad and Iraqi Kurds over territory and resources, and the rivalry between two of the country's main Kurdish parties.
An AFP correspondent saw Kurdish security personnel with black Humvee armoured vehicles and trucks deployed at the entrance to the North Oil Company in the northern province of Kirkuk.
The forces halted pumping through the pipeline to the Turkish port of Ceyhan, but "pumping operations gradually resumed after noon today, hours after they stopped," a senior North Oil Company official said.
"All employees and workers and technicians returned to their work," the official said.
A top official in the Patriotic Union of Kurdistan (PUK) party, whose forces deployed at the company, described the move as a message to the federal government and threatened further escalation.
"The entry of the military force to the North Oil Company came to send a message to Baghdad, saying it should establish an oil refinery in Kirkuk," Asso Mamand told AFP.
"We give Baghdad a period of one week to set up an oil refinery in Kirkuk (and) stop the decision to send oil to other Iraqi provinces," Mamand said, threatening "to take complete control of the North Oil Company" if this is not done.
An agreement on establishing a new refinery in Kirkuk was signed earlier this year, but work has yet to begin.
The Kurdistan Democratic Party (KDP), the ruling party of Iraq's autonomous Kurdish region, asked its rival for an explanation.
"We demanded that the Patriotic Union of Kurdistan announce their demands and clarify the reason for the presence of these forces inside the North Oil Company," said Mohammed Khorsheed, the KDP's top Kirkuk official.
While oil-rich Kirkuk province is officially part of federal Iraq, most of it has been controlled by the PUK since federal forces fled the sweeping 2014 offensive by the Islamic State group, and the Kurds want to keep it.
The conflict with IS has pushed that and other territorial disputes between the Kurds and Baghdad to the background, but they will likely reemerge after the end of major military operations against the jihadists.
Iraqi Kurdistan is also riven by internal political rivalries that would undermine any move toward a long-mooted declaration of independence for the region.