Washington wants "the Iraqi government to halt the violence against protesters and fulfill President (Barham) Saleh's promise to pass electoral reform and hold early elections," the White House said in a statement.

"The United States is seriously concerned by continued attacks against protestors, civic activists, and the media, as well as restrictions on internet access, in Iraq," it said.

Mass rallies calling for an overhaul of the ruling system have rocked the capital Baghdad and the Shiite-majority south since October 1, but political forces closed ranks this week to defend the government.

The consensus among the elite seems to have paved the way for a crackdown.

Parliament's human rights committee says that 319 people have been killed since protests first erupted, including demonstrators and security forces.

The committee said snipers were active near protest sites and hunting rifles were used against demonstrators as well.