According to the
Boston Globe five Shi'ite members of the IGC have refused to sign the new Basic Law of Iraq that was to have governed the interim quasi-sovereign Iraqi government. They are complaining that the Basic Law has forced them to give too many territorial and autonomy concessions to the Kurds and that the central government is too weak.
I have a hard time seeing what incentive they have to sign away their political goals. In the short term they know that Bush and Rove want something, anything signed and delivered by July 1, 2004. Bush/Rove do not care what that something is, they just need a nice signing ceremony for a campaign commercial and to allow US troops to withdraw from the cities in order to minimize US casualties and bad headlines. They know that Bush has very little levarage besides immediately pulling the US Army out, which he can not do without massive long term consequences and short term political pain.
Therefore, the US will try to cave to the current group of hardliners. This action will almost surely infuriate either the Kurds or the Sunni Arabs who must realize the same dynamic would be at play if they are to threaten to veto a revised interim law.