As he attempts to put the final touches to a government of national unity that was supposed to help heal the country's divisions, Iraq's new prime minister has been confronted by sectarian and factional cracks in his coalition and even within his own Shia bloc.

It is almost three weeks since Nuri al-Maliki announced the bulk of his cabinet but he is still trying to fill the most politically sensitive positions, the interior and defence posts, which control government forces that both Sunni and Shia fear can be used as weapons against them.