A cross-sectarian coalition led by Iyad Allawi, a former prime minister, won two more seats than a mainly Shia bloc headed by Nouri al-Maliki, the incumbent premier.
Al-Maliki's State of Law bloc won 89 seats in Iraq's 325 seat parliament compared with Allawi-led Iraqiya's 91 seats.
Al-Maliki has a announced a union between his party and the Iraqi National Alliance, which finished third.
Together, this two party bloc will control 159 seats, just short of a parliamentary majority.
Allawi has warned that an alliance excluding his Iraqiya party, which has strong support from the minority Sunni community, could trigger renewed sectarian violence.
One candidate from the Iraqi National Alliance was not approved, as the court awaited information from the electoral commission surrounding his candidacy.
With the court's approval of election results, the president now has 15 days to call the new parliament to convene.