Thousands have rallied in Baghdad in support of Iraqi Shia cleric Muqtada al-Sadr, who has taken the lead role in protests demanding government reforms.

Al-Sadr's associate, Sheik Asad al-Nasiri, delivered a message from the cleric at a rally on Friday in the Iraqi capital, giving Prime Minister Haider al-Abadi 24 hours to implement wide-ranging reforms such as installing technocrats in key political positions.

Otherwise, the message says, the protesters will not limit themselves to sit-ins outside the heavily fortified Green Zone in Baghdad, where the government is headquartered and where al-Sadr's followers demonstrated last week.

The weekly rallies in Baghdad are meant to put pressure on Iraq's political leadership.

The prime minister's efforts to implement reform have been thwarted by his own political mis-steps as well as the country's increasingly sectarian politics.

Last month, Abadi, now a year and a half into his four-year term, said he wanted to replace his ministers with technocrats to challenge the system of patronage that encourages corruption by distributing posts along political, ethnic and sectarian lines.

Sadr and his supporters have held regular demonstrations demanding reforms to tackle corruption, which is eating into Baghdad's resources even as it struggles with falling revenues due to a slump in global oil prices and high spending caused by the costs of war against the Islamic State of Iraq and the Levant (ISIL)

Source: Agencies