Al-Rubaie was reading out a statement on behalf of al-Sadr.
"We found it necessary to issue an order to the ministers of the Sadrist bloc to withdraw immediately from the Iraqi government," al-Rubaie told a news conference.
The move is unlikely to bring down the government of Nuri al-Maliki, Iraq's prime minister, but it could create tensions in his fractious government of national unity.
'No need for timetable'
The Sadrists have said they would remain in parliament.
"The chances of success [in Iraq] are essentially zero because the Iraqi people have no voice"
Non Sequitur, Cadiz, Spain
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