Iraqi cleric Moqtada Sadr on Sunday entered the perimeter of Baghdad's fortified "Green Zone" and began a sit-in to ramp up pressure for reforms.

The symbolic move by the young Shiite cleric comes after thousands of his supporters have been camping outside the restricted area's entrances for more than a week.

Sadr wants Prime Minister Haider al-Abadi to enact reforms tackling corruption and announce a technocratic government to replace the current cabinet of party-affiliated ministers.

In his most recent address, Sadr had said Abadi should announce new measures by Saturday or face further pressure from the street.

Late in the afternoon on Sunday, Sadr walked into the so-called Green Zone, not only unopposed but even apparently assisted by members of the security forces.

"I will enter the Green Zone alone... and will sit in the Green Zone while you sit at the gates," he said in an impromptu press conference moments earlier.

The Green Zone covers a sprawling area by the Tigris in central Baghdad. It houses the prime minister's office, parliament as well as the US embassy, which is the world's largest.

He asked his supporters to be steadfast in their peaceful protest to push for reforms and warned against any violent behaviour.

"Whoever harms the security forces harms me personally," he said.

Sadr's entourage set up two foam mattresses and a small marquee to shelter him from the rain as the cleric prepared to begin his sit-in protest.

Sadr had previously given Abadi a 45-day ultimatum that expires on Tuesday but the premier has to grapple with leaders from his own political bloc who are both reluctant to relinquish their positions and rattled by Sadr's return to the spotlight.

UN chief urges Iraq politicians to back PM's reforms
Baghdad (AFP) March 26, 2016 - UN chief Ban Ki-moon on Saturday urged Iraq's politicians to support embattled Prime Minister Haider al-Abadi's reform drive.

Speaking in Baghdad on his eighth visit to Iraq as secretary general of the United Nations, Ban emphasised the need for national reconciliation.

"I call on all political leaders here today to continue your efforts towards a single, unified vision to advance national reconciliation in Iraq," Ban said in an address to parliament.

He said such a vision should include the justice and accountability law, a controversial amnesty law and the establishment of a national guard.

Abadi is facing tough resistance from his own political camp over several of these issues.

"This spirit of compromise must extend to making sure that the executive and legislative branches, including the parliamentary blocs, work closely together to support the prime minister, as he implements the needed reforms to address the multiple crises you face," Ban told lawmakers.

Ban, who had last visited the Iraqi capital in March 2015, was travelling with World Bank chief Jim Yong Kim and Islamic Development Bank head Ahmad al-Madani.

"This is a joint and combined demonstration of our support for the noble efforts, sometimes very difficult efforts of the Iraqi government in first of all securing peace and stability through national reconciliation and socio-economic reforms, through inclusive dialogue," Ban said.

A drop in oil prices has had a devastating effect on the economy of Iraq, already strained by the cost of the fight against the Islamic State group.

As areas are gradually retaken from the jihadists in intense battles, Baghdad is left with little to spare on the reconstruction of ravaged cities.

The head of the World Bank pledged his institution's support to Iraq as it begins rebuilding reconquered areas.

The World Bank recently granted Iraq a $1.2 billion loan to help it weather its financial crisis -- the institution's largest ever direct budget support in the region.

"A clear commitment to reforms would build confidence, which he hoped would lead to greater international support for coping with the impact of low oil prices," a statement from Kim's office said.

Supporters of Shiite cleric Moqtada Sadr have been camping outside entrances to the fortified Green Zone -- which houses the country's main institutions -- for more than a week.

Sadr says the goal of the protest is to support Abadi's reform drive and demand more measures in the fight against corruption.

He has given Abadi until Tuesday to present names of technocrats for a reshuffled cabinet.

But his move leaves Abadi's government hanging by a thread, with powerful Shiite leaders in his own bloc both reluctant to relinquish their positions and rattled by Sadr's return to the spotlight.