The Iraqi government announced Thursday a three-day mourning for the death of the leading Iraqi Shiite cleric and politician Abdul Aziz al-Hakim, the Iraqi official television reported.

"The Iraqi government announced three-day national mourning starting from Thursday for the death of Sayyed Abdul Aziz al-Hakim, " the state-run Iraqia channel said.

Hakim, the head of one of Iraq's most powerful Shiite parties, the Supreme Iraqi Islamic Council (SIIC), has died in a Tehran hospital on Wednesday.

He was diagnosed with lung cancer in May 2007 after medical tests in the United States, but he preferred to receive treatment in Iran.

Hakim, 59, is a prominent Shiite theologian and politician, who headed the SIIC, the largest political party in the Iraqi parliament.

After the U.S.-led invasion in 2003, Hakim became a member of the U.S.-appointed Iraqi Governing Council and served as its rotating presidency in December 2003.

In August 2003, he replaced his brother Mohammed Baqir al- Hakimas the leader of the SIIC Shiite party, then named the Supreme Council for the Islamic Revolution in Iraq.