The United Nations is investigating allegations of corrupt contracts linked to its peacekeeping missions.



The contracts amount to $610 million.



An internal report claims that procurement staff were involved in cases of fraud and misconduct in Haiti and the Democratic Republic of Congo.



Other UN missions in Africa are also under investigation.



The UN came under intense criticism in 2005 after an investigation into the oil-for-food programme with Iraq.



It was discovered that the scheme was mismanaged and was riddled with corruption.