"If Bremer rejects Ayatollah Sistani's opinion, he would issue a fatwa depriving the US-appointed council of its legitimacy," Ayatollah Mohammed Baqer al-Mohri told Abu Dhabi television. "After this, the Iraqi people will not obey this council. This US plan is not in line with Sistani's views."
In Basra, huge crowds walked through the streets, some arm in arm, chanting "No to America" and carrying portraits of Ayatollah Sistani. The protest will come as another uncomfortable warning to the US that, for the second time since the war, it may need to rework its political programme for Iraq. Mr Bremer is flying to Washington for urgent consultations.
As always, Juan Cole has a lot more.