Iraq's new parliament elected two months ago is scheduled to meet on July 1 to begin forming a new government.
The announcement comes in a decree issued on June 26 by Iraqi President Jalali Talabani.
Iraqi Prime Minister Nuri al-Maliki is under international pressure to form a more inclusive government to undermine support for Sunni militants who have seized northern cities.
That message was delivered again by British Foreign Secretary William Hague during a visit to Baghdad on June 26.
The United States and its allies are pushing for the creation of a government that can draw support among Iraq's Sunni minority, which has been alienated by Maliki, seen as a partisan Shi'ite.
Maliki conceded to Hague that political measures along with military action were needed to defeat the Sunni rebels led by the Islamic State in Iraq and the Levant, an Al-Qaeda offshoot.
Meanwhile, Iraqi forces launched an assault to retake the city of Tikrit from the militants on June 26.
Eyewitnesses say battles were raging in the city, which fell to Sunni militants two weeks ago.