Kurdish ministers said they were boycotting meetings of Iraq's caretaker cabinet and authorities in Baghdad halted cargo flights to two Kurdish cities, in an escalating row between the Shi'ite-led central government and Kurdish leaders, Reuters reported.
The suspension of attendance was in protest at Prime Minister Nuri al-Maliki's "provocative" branding of the Kurdish provincial capital Arbil as a haven for the Islamic State group and other militants, the ministers said in a statement on Thursday.
However, the officials would continue running their ministries and "did not pull out from the government," a senior Kurdish official speaking on condition of anonymity told Reuters.
The ministers did not mention a timeline for their boycott or terms for their return, but they called for an inclusive national government. Iraq's cabinet holds scheduled meetings every Tuesday and exceptional meetings can be called at other times.
Hours later, the head of Iraq's civil aviation authority Nasser Bandar told Reuters cargo flights to Arbil and Iraq's second main Kurdish city, Sulaimaniya, had been suspended until further notice. He said passenger flights were unaffected.
With an Islamist insurgency raging in the country's Sunni provinces, the United States and other countries have called for politicians in Baghdad to set up a more inclusive government following a parliamentary election in April.
But the new legislature has failed to agree on leadership for the country, leaving Maliki in power as a caretaker while Shi'ite and Kurdish leaders trade accusations over the insurgency.
Relations hit a low on Wednesday when Maliki accused the Kurds of allowing Arbil to be used as a center for Islamic State and others, including former members of Saddam Hussein's now-banned Baath Party.
"We will never be silent about Arbil becoming a base for the operations of the Islamic State and Baathists and al Qaeda and the terrorists," Maliki said..
Sunnis and Kurds demand Maliki leave office, but he shows no sign of agreeing to step aside. The Kurds are now closer than ever to abandoning Iraq altogether, with Massoud Barzani, leader of their autonomous region, calling last week for his parliament to prepare a referendum on independence.
Maliki's relationship with Barzani has steadily deteriorated since last month, when Islamic State and allied Sunni armed groups seized swathes of northern and western Iraq.
Many Sunni Muslims who fled the mostly Sunni northern city of Mosul during the militants' offensive have ended up in Iraqi Kurdistan, with leading Sunni political figures hated by Maliki now frequenting Arbil.
Maliki, meanwhile, has accused the Kurds of exploiting the crisis to push for statehood. Kurdish forces exploited the turmoil to seize control of the city of Kirkuk and its huge oil reserves a month ago, achieving a long-held dream.
Responding to what he called Maliki's "void" accusations, Barzani's spokesman said on Thursday that Maliki "has been afflicted by a true hysteria and lost his balance as he tries as hard as he can to justify his errors and failure and make others responsible for it."
Omaid Sabah said Arbil "is a refuge now for all those fleeing his dictatorship" and called for Maliki to apologize to the Iraqi people for destroying the country.
"The person who destroyed it cannot save it from crises."