The Coordination Framework, an alliance of Shiite factions with varying links to Iran, said in a statement that it "decided, by majority vote, to nominate" Maliki for the position "as the candidate of the largest parliamentary bloc".

The statement spoke of Maliki's "political and administrative experience and his record in running the state".

A shrewd politician, Maliki, 75, has long been a central figure in Iraq's politics and its only two-term prime minister (2006-2014) since the US invasion of 2003, which ended decades of rule by the autocratic Sunni president Saddam Hussein.

Since the invasion and by convention in Iraq, a Shiite Muslim holds the powerful post of prime minister, a Sunni is parliament speaker, and the largely ceremonial presidency goes to a Kurd.

After Iraq's November general election, the Coordination Framework, which includes Maliki, formed the majority bloc.

Soon after, it held heated talks to choose the next prime minister, along with other discussions with Sunni and Kurdish parties regarding other posts.

Iraq's parliament chose a speaker last month and should convene next to elect a new president, who will then appoint a prime minister to replace the incumbent Mohammed Shia al-Sudani.

Maliki, leader of the State of Law Coalition, remains influential in Iraqi politics despite his controversial past, including widespread accusations of corruption, stoking sectarian tensions, and failing to stop the Islamic State group.