(AFP) -- "The two main roads connecting Arbil and Dohuk to Mosul were cut off on Thursday with sand embankments as a precautionary measure after we detected an increase in deployments and movements of Iraqi forces near the front line with the peshmerga," he said.
The move came after Kurdish authorities said late on Wednesday they feared Iraqi government forces and allied paramilitary units were preparing to launch an assault on the autonomous northern region.
"We're receiving dangerous messages that the Hashed al-Shaabi (paramilitary forces) and federal police are preparing a major attack from the southwest of Kirkuk and north of Mosul against Kurdistan," the Kurdistan Regional Government's Security Council said.
The warning came amid spiralling tensions between Iraq's Kurds and central authorities in the wake of last month's Kurdish independence referendum.
In the oil-rich region of Kirkuk, which is disputed between the Kurds and Baghdad, a local commander told AFP there were no immediate signs of movement.
"We have seen no unacceptable movement on the part of Iraqi forces," Wasta Rasul, the commander of peshmerga forces in southern Kirkuk, told AFP.
He said the peshmerga were in meetings with the US-led coalition that has intervened in Syria and Iraq against the Isis group and that "its aircraft are monitoring the situation carefully".
The coalition has worked with the peshmerga, as well as Iraqi pro-government forces, in the battle to oust Isis from areas it seized in Iraq in mid-2014.
Security sources said that Iraq's elite Counter Terrorism Service (CTS) and Rapid Response Force had deployed more forces near Rashad, a village some 65 kilometres (40 miles) south of Kirkuk, near peshmerga positions.
Asked by AFP, the spokesman for Iraq's Joint Operations Command, refused to confirm or deny any preparations for an offensive.
"What I can say is that our forces in Hawija have accomplished their duty and have started to clear the region of explosives and restore the law in order to allow people to go home," said the spokesman, Brigadier General Yahiya Rassul.
Iraqi forces last week retook control of Hawija, one of Isis' last enclaves in the country, which is close to Kurdish majority areas.
Baghdad and Arbil have been locked in a stand-off since voters in Kurdistan overwhelmingly opted two weeks ago for independence in a referendum that the central government slammed as illegal.
Iraq has cut Kurdistan off from the outside world by severing air links to the region, while neighbouring Turkey and Iran have threatened to close their borders and block oil exports.
(Photo: Kurdish peshmerga forces, show here voting in last month's independence referendum, are reported to have blocked roads from other parts of Iraq to the autonomous Kurdistan region, AFP)