Iraq's Shiite Prime Minister Nouri al-Maliki ordered Sunni Vice President Tariq al-Hashemi arrested on charges related to terrorism. Hashemi said the charges are fabricated and he wants the case transferred to the Kurdish region of Iraq, which he said is a neutral party.
Maliki, in a statement translated by CNN, said it was the "duty of all parts of a federal state" to cooperate with the central government's wishes.
The arrest warrant for Hashemi was issued the day after U.S. forces left the country. U.S. Vice President Joe Biden spoke Wednesday with Iraq's prime minister and speaker of Parliament to discuss the acrimonious political climate in the country.
Washington, the White House said in a report of the phone call, is watching political events in Iraq "closely."
"The vice president also stressed the urgent need for the prime minister and the leaders of the other major blocs to meet and work through their differences together," the White House statement added.
Masoud Barzani, president of the Kurdistan Regional Government, warned the situation was developing into a critical matter for Iraq immediately after U.S. forces left.
"I call for an urgent national conference to avoid a collapse of the political process," he said in a statement.