The court found that the decision by parliament to order a manual recount in response to allegations of electoral fraud did not violate the constitution, its president Medhat al-Mahmud told a news conference.

All of the roughly 11 million ballots, including those of voters living abroad, displaced persons and security forces, must be recounted, Mahmud said.

The May 12 vote was won by cleric Moqtada Sadr's electoral alliance with communists, as long-time political figures were pushed out by voters hoping for change in a country mired in conflict and corruption.

The result was contested -- mainly by the political old guard --  following allegations of irregularities in the election, Iraq's first since the defeat of the Islamic State group.

The vote saw a record number of abstentions as Iraqis snubbed the corruption-tainted elite that has dominated the country since the US-led invasion of 2003 toppled Saddam Hussein.