UN peacekeepers commonly pay for sex with cash, dresses, jewellery, perfume, mobile phones and other items despite a ban on such relationships, a draft UN report has concluded.

The draft study by the UN Office of Internal Oversight Services (OIOS), obtained by Reuters news agency and since seen by Al Jazeera, says surveys of hundreds of women in Haiti and Liberia found their reasons for selling sex included hunger, poverty and lifestyle improvement.

"Evidence from two peacekeeping mission countries demonstrates that transactional sex is quite common but underreported in peacekeeping missions," concluded the OIOS draft dated May 15.

The UN currently has more than 125,000 troops, police and civilians deployed in 16 operations around the world.

The OIOS draft report also notes that "the number of condoms distributed, along with the number of personnel undergoing voluntary counselling and confidential testing for HIV ... suggest that sexual relationships between peacekeeping personnel and the local population may be routine".

It said a UN bulletin issued in 2003 banned transactional sex by peacekeepers, in part because it undercuts the organisation's credibility in areas where it is serving.

The OIOS draft said 480 allegations of sexual exploitation and abuse had been made between 2008 and 2013, of which one-third involved children.

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It said missions in Democratic Republic of Congo, Liberia, Haiti and South Sudan accounted for the largest numbers of accusations.

In 2014 it said 51 allegations of sexual exploitation and abuse had been made against UN peacekeepers.

States providing troops to UN missions have the primary responsibility to investigate allegations against their soldiers and police.

"Despite continuing reductions in reported allegations, that are partly explained by underreporting, effectiveness of enforcement against sexual exploitation and abuse is hindered by a complex architecture, prolonged delays, unknown and varying outcomes, and severely deficient victim assistance," OIOS said.

'Fundamental problems'

Speaking to Al Jazeera from London on Thursday, Anneke Van Woudenberg, Africa deputy director at Human Rights Watch, the New York-based rights monitor, said she was not surprised by the findings in the draft UN report.

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"This is something that we have seen in many countries of the world where the UN is operating and it has been a problem that has been going on for many years," she said.

"The UN has tried to tighten up on it, but it has got a couple of fundamental problems - one of which is that there is immunity from prosecution for peacekeepers that are deployed on UN peacekeeping missions.

"If those peacekeepers commit crimes [while on mission], they cannot be held to account in those countries. They can only be held to account in their home countries, and far too often this immunity is like a protective cloak."

The draft report included a response by the UN Departments of Peacekeeping Operations and Field Support.

They regretted that OIOS did not evaluate prevention efforts and only focused on enforcement and remedial assistance efforts.