A UN report on its failure to protect civilians in Sri Lanka’s civil war will have “profound implications” for the global body, UN chief Ban Ki-moon says.

Publishing the damning internal report, which was leaked to the BBC, Mr Ban said lessons had to be learnt.

A senior panel will advise him on how to prevent the system breakdowns that led to “grave failure” in Sri Lanka.

The government and Tamil rebels are accused of war crimes in the conflict, which ended in May 2009.

The 26-year war left at least 100,000 people dead. There are still no confirmed figures for tens of thousands of civilian deaths in the last months of battle.

An earlier UN investigation said it was possible up to 40,000 people had been killed in the final five months alone. Other estimates say the number of deaths could be even higher.

The government’s own estimate of deaths in the final few months is 9,000.

The internal review concluded that various UN agencies, including the Security Council and Human Rights Council, had failed at every level to meet their responsibilities in the last months of the civil war in Sri Lanka.

In particular it highlighted the organisation’s reluctance to publish casualty figures and its decision to withdraw staff from the war zone, as well as its failure to report evidence of widespread government shelling.

As a result, the report recommends a comprehensive review of the UN’s implementation of humanitarian and protection mandates.

“I am determined that the United Nations draws the appropriate lessons and does its utmost to earn the confidence of the world’s people, especially those caught in conflict who look to the organisation for help,” Mr Ban said in a statement.

He added that events in Syria were the latest reminder that the UN’s core mission to protect civilians was crucial.

The report had been made public, Mr Ban said, as “transparency and accountability are critical to the legitimacy and credibility of the United Nations”.

The UN’s former humanitarian chief, John Holmes, has criticised the report.

Mr Holmes said the UN faced “some very difficult dilemmas” at the time and could be criticised for the decisions it had taken.

“But the idea that if we behaved differently, the Sri Lankan government would have behaved differently I think is not one that is easy to reconcile with the reality at the time,” he told the BBC’s Newshour programme earlier this week.

Benjamin Dix, who was part of the UN team that left, told the BBC he disagreed with the pull-out.

“I believe we should have gone further north, not evacuate south and basically abandon the civilian population with no protection or witness,” Mr Dix said.

“As a humanitarian worker, questions were running through my mind: ‘what is this all about? Isn’t this what we signed up to do?'”

Hundreds of thousands of Tamil civilians remained in the war zone, says the BBC’s chief international correspondent Lyse Doucet, who was the first to see the leaked report.

The civilians were exploited, by both sides, our correspondent says: forcibly recruited by Tamil Tigers or used as human shields; or under indiscriminate government fire.

Despite a “catastrophic” situation on the ground, the new UN report points out that in the capital Colombo “some senior UN staff did not perceive the prevention of killing of civilians as their responsibility – and agency and department heads at UNHQ were not instructing them otherwise”.

It says there was “a continued reluctance” among UN personnel in Sri Lanka “to stand up for the rights of people they were mandated to assist”.

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http://www.bbc.co.uk/news/world-asia-20331872