"The government of Prime Minister Mohammed Shia al-Sudani has obtained the confidence of the National Assembly," his office said in a statement after the vote.

Sudani was chosen earlier this month to form a new government following months of infighting between key Shia Muslim factions that has paralysed political life for months.

The movement of firebrand cleric Moqtada Sadr, Sudani's rival in Iraq's majority Shia camp, refused to join the government.

"Our ministerial team will shoulder the responsibility at this critical period, in which the world is witnessing tremendous political and economic changes and conflicts," the statement read.

Those changes will "add new challenges to our country, which is already suffering from accumulated crises, that have had economic, social, humanitarian and environmental impacts on our citizens", it added.

Sudani, nominated on October 13, had the backing of the Coalition for the Administration of the State, which includes the Coordination Framework, an alliance of powerful pro-Iran Shiite factions that hold 138 out of 329 seats in parliament.

Other members include a Sunni grouping led by parliament speaker Mohammed al-Halbussi, and two key Kurdish parties.

Under a power-sharing system adopted in Iraq in the aftermath of the 2003 US-led invasion, cabinet posts are shared between Iraq's ethnic and confessional communities.