The political bloc of radical Shi'ite cleric Moqtada al-Sadr say it will withdraw from Iraq's government to protest the prime minister's failure to support a timetable for US troops to leave the country.
Officials of the party, which has six of Iraq's 37 cabinet ministers, said Sunday the ministers would withdraw on Monday. There has been no response from the government of Prime Minister Nuri al-Maliki.
Meanwhile, Iraqi authorities say a wave of bombings Sunday in mostly Shi'ite areas of Baghdad killed at least 34 people.
In another incident Sunday, two British military helicopters crashed north of Baghdad, killing two soldiers and injuring five. Officials said the helicopters may have collided.
Near the northern city of Mosul, four Iraqi soldiers were killed in an attack on a police base, and gunmen killed four members of a Kurdish family.
The blasts in Baghdad come one day after a bomb in Karbala killed 40 people near one of the most sacred sites in Shi'ite Islam, the Imam Hussein Shrine.
The US military said a Marine and a soldier were killed in separate incidents Saturday.