Two large Shia groups which performed strongly in the Iraqi elections in March have merged to form the biggest alliance in the new parliament.
The merger is to be known as the National Alliance.
It is made up of outgoing Prime Minister Nouri Maliki's State of Law coalition - which was runner-up in the election in March - and the third-placed Iraqi National Alliance, along with other Shia factions.
As allies, they will be four seats short of an absolute majority in parliament, but well ahead of the 91 seats held by the al-Iraqiyya group which came first in the elections.
The new parliament opens on Monday. No prime minister has been announced yet.