The brief session brings to 17 the number of filled posts in Prime Minister Adel Abdel Mahdi's 22-ministry cabinet. The other 14 were approved by parliament in late October.

New Higher Education Minister Qusay al-Suheil, 53, is a member of former premier Nuri al-Maliki's State of Law bloc.

Planning Minister Nuri al-Dulaimi, 51, is an Iraqi Islamic Party member while Minister of Culture Abdulamir Al-Hamdani, a 51-year-old archaeologist, is backed by pro-Iran force Asaib Ahl al-Haq.

After the speedy vote, legislators adjourned their session to Thursday afternoon.

The five empty posts include the powerful ministers of defence and interior, seen as the primary stumbling blocks to a full cabinet.

Abdel Mahdi has proposed Faysal al-Jarba and Faleh al-Fayyadh as ministers of defence and interior respectively, both backed by parties close to Iran.

But rival Sunni political parties are deeply divided over Jarba.

Saeroon, the coalition headed by populist cleric Moqtada al-Sadr and the largest bloc in parliament, is fiercely opposed to Fayyadh's nomination.

Last week, he told journalists the ongoing dispute over the unfilled ministries was "not his decision."

"We were free to choose eight or nine ministers, and the rest are the results of political agreements," he said.

"When it comes to the interior and defence, these were the choices of the political blocs, not of the premier."

As government formation drags on, observers have wondered whether Abdel Mahdi could step down, further destabilising a country struggling to rebuild after three years of fighting against the Islamic State group.