The Iraqi COR will then begin the process of government formation, the directive noted.
On Wednesday, Prime Minister Nouri al-Maliki urged sectarian factions to overcome their differences in the face of violent instability fueled by Islamic State of Iraq and Syria-led attacks.
"We desperately need a united national stance to defy terrorism," the prime minister said during his televised address.
U.S. Secretary of State John Kerry and others have championed a two-track approach to the crisis, militarily and politically: fight ISIS and form an inclusive new government in line with Iraq's constitutional mandates.
"The Iraqi state is facing an existential threat, with huge ramifications for the true future stability and freedom of this country," said Hague. "The single most important factor that will determine whether or not Iraq overcomes this challenge is political unity."