"At the request of the Americans, and to preserve the life of our military, the commander of the Ukrainian contingent decided to evacuate the civil administration staff and Ukrainian troops from Kut," the ministry said in a statement.

"The operation began at dawn on Wednesday ... under escort from attack helicopters," the ministry added.

Members of the Iraqi civil defense forces already on Tuesday had said that Sadr's militia controlled Kut, 180 kilometres (110 miles) south of Baghdad, but this was denied by the Ukrainian military.

According to the Ukrainian defence ministry, fighting lasted for around 24 hours and left several dozen Iraqis dead and one Ukrainian soldier -- the first to be killed in combat in Iraq.

The Ukrainian soldiers retreated to their base outside Kut in the Iraqi province of Wasit. "The situation is calm and under control in the rest of the province," the defence ministry said.

Ukraine has some 1,650 troops in Iraq, part of a 9,000-strong Polish-led force controlling a swathe of the country south of Baghdad.

Last month Kiev said it was not planning to pull out its troops despite Spain's decision to recall its 1,300 soldiers from the war-torn country by the end of June unless they come under UN command.

The Spanish troops also serve in the Polish-led sector.

WAR.WIRE