UNITED NATIONS - Lakhdar Brahimi, a veteran diplomat who headed a global study on the security of U.N. staff members, has said that the world's "big powers" have tarnished the world body's image of neutrality, at a time when the world body is increasingly threatened by terrorist attacks. Lakhdar Brahimi, a former Algerian foreign minister who helped form governments in Iraq and Afghanistan, has just completed a survey of U.N. security in 20 duty stations around the world. He told reporters at the United Nations that the U.N. is perceived by some as a tool of powerful members, rather than an unbiased advocate for all nations. His team was told time and again by U.N. staff members that the United Nations is no longer seen as impartial. "Wherever the panel went, they were told by the U.N. people - and this is not only in Arab and Muslim countries but in Geneva, Rome, Nairobi and Sri Lanka - that there is this phenomenon these last few years that the U.N. is not perceived by a lot of people as impartial and independent," Mr. Brahimi said. "What's happening in the Middle East has a lot to do with it, but it's not only that. The big powers are using their muscles to influence the United Nations and that the United Nations is, not always, but time to time does not speak on behalf of its 192 members." Mr. Brahimi's 103-page report, released last week, was undertaken after a  group affiliated with al Qaeda blew up the U.N. headquarters in Algeria in December. Twenty-two people, including 17 U.N. staffers, were killed and 40 wounded in an attack that was foreseen by U.N. and Algerian government officials. The survey touches briefly on Algeria, but also broadly outlines flaws in the U.N. security structure and culture, plummeting respect for the United Nations, failure by host countries to communicate and guard against threats to the organization, and a lack of recognition by the Security Council and other U.N. bodies of how their actions put staff in the field at risk. The head of U.N. Department of Safety and Security, David Veness, who wrote his own confidential assessment of the Algiers bombing, resigned last week. His inquiry makes clear that the Algerian government failed to take adequate precautions, and senior U.N. officials failed to demand protection even after an Islamic terrorist group began threatening the organization. Particularly damaging to the U.N. reputation, Brahimi said Monday, was that it took a full month for the Security Council to demand a cease-fire when Israel invaded southern Lebanon in July 2006. Brahimi's appointment was the only way the Algerian government would have consented to an investigation, U.N. officials said on the condition of anonymity because of the sensitivity of the issue. "I'm not sure that the choice of an Algerian to investigate the bombing in Algiers is ideally the best choice," said British Ambassador John Sawers. "Clearly [Algeria] did not fulfill all its responsibilities. Had they done so, the bombing wouldn't have happened. I'm not sure the report captures that fully." Mr. Brahimi, 64, gently rebuffed the suggestion of favouritism. "I never thought I was picked because I am an Algerian. I think, vainly, that I have some other qualifications beside my nationality," Mr. Brahimi said. He has led U.N. efforts from South Africa to Haiti and taken on dozens of diplomatic assignments for the United Nations.