BAGHDAD - Iraqi Prime Minister Haider al-Abadi proposed scrapping top government posts and privileges on Sunday in an ambitious reform drive sparked by swelling popular anger over corruption and poor governance.

The proposed reforms followed weeks of demonstrations and a call for tougher reform measures from top cleric Grand Ayatollah Ali al-Sistani, who is revered by millions of Iraqis.

Amid a major heatwave that has seen temperatures top 50 degrees Celsius (120 degrees Fahrenheit), protesters have railed against the poor quality of services, especially power outages that leave Iraqis with only a few hours of government-supplied electricity per day.

But even with popular pressure and Sistani's backing, the entrenched nature of corruption in Iraq and the fact that parties across the political spectrum benefit from it will make any efforts to change the system extremely difficult.

One of the most drastic proposals outlined in an online statement by Abadi was the call for the elimination of the posts of vice president and deputy prime minister "immediately".

The cabinet approved the reform plan on Sunday, Abadi's office said, but changes such as abolishing the posts would apparently require the constitution to be amended, which would necessitate parliamentary action. The three vice presidential posts, which come with more privileges than responsibilities, are held by former top officials - Abadi's predecessor and main rival Nuri al-Maliki, ex-parliament speaker Osama al-Nujaifi and former premier Iyad Allawi.

Maliki and Nujaifi said on Sunday that they supported the reform drive, indicating that the proposed changes may have been made as part of a deal they endorsed.

"I renew my support for the reforms that are needed," said Maliki, while Nujaifi announced his "support for and welcome of the decisions".

Abadi also called for a major overhaul of the way senior officials are selected, saying that all "party and sectarian quotas" should be abolished, and the candidates chosen by a committee appointed by the premier.

No quotas are enshrined in the constitution, but the patronage system grants many government jobs according to sect and party affiliation rather than merit.

Abadi also said there should be a "comprehensive and immediate reduction" in the number of guards for officials.

This has long been a problem, with some officials having massive personal protection units, and others hiring fewer than the allotted number and pocketing the rest of the allowance.

Abadi called for an end to "special provisions" for senior officials, both current and retired.

He did not specify, but large salaries, government-provided vehicles and generous retirement benefits have all long been bones of contention between the authorities and average Iraqis.

Old and current graft cases should also be reopened under the supervision of a high commission for fighting corruption, Abadi said.

Sistani called Friday for Abadi to take "drastic measures" against corruption, saying that the "minor steps" he had announced were not enough.

One of those whose position is being axed is Bahaa al-Araji, the much-reviled deputy prime minister in charge of energy.

Chief prosecutor Abdel Sattar Birakdar's office announced Sunday that the anti-corruption court was ordered to investigate allegations against him.

Araji, a member of prominent cleric Moqtada al-Sadr's party, announced his resignation but said he was ready to fight graft accusations in court.

Abadi's efforts face major challenges. "The entire system of government is rotten. The constitution is decrepit, the legal framework is woefully inadequate and the political class is utterly corrupt and incompetent," said Zaid al-Ali, author of "The Struggle For Iraq's Future".

"All political parties that are part of government profit directly from the current system, which is why it has remained unchanged since 2005," said Ali, a constitutionalist.

The latest major protest was on Friday, with thousands in Baghdad and the south venting their anger at authorities.

Various parties and politicians have sought to align themselves with the protesters - at least in their rhetoric - to take advantage of the movement and mitigate the risk to themselves.

People have protested over services and corruption before, but the demonstrations failed to bring about significant change.

Some activists said the demonstrations should go on, with a group planning to gather in central Baghdad later Sunday. "I consider this a start but we have to monitor very closely how serious and credible the implementation of the reforms will be," said Nabil Jassim, a journalist and one of the leading organisers of the protests.