Iraq's most influential Shi'ite cleric, Grand Ayatollah Ali al-Sistani, has backed the country's Prime Minister-designate Haidar al-Abadi.

Sistani, in comments on August 15, said the transition was a rare opportunity to resolve political and security crises.

He also said battling corruption should be one of the priorities of the new government.

In a national televised address earlier on August 15, Prime Minister Nuri al-Maliki announced that he would step down and support Abadi to "safeguard the high interests of the country."

Maliki has been prime minister since 2006.

He has been widely accused of fueling sectarian tensions as Iraq battles Islamist militants.

He had previously rejected Abadi's nomination and said he would go to court to stay in his post.

The United States and UN Secretary-General Ban Ki-moon welcomed his decision to step down.

Based on reporting by Reuters