The world should not be swayed by this campaign of vilification against the UN

The United Nations must treat the conclusions of Paul Volcker's interim report on the Iraqi oil-for-food programme with the utmost seriousness. The report, by the former chairman of the US Federal Reserve, makes it clear that the conduct of Kofi Annan fell below that expected of someone in his position. The UN secretary general should have been more alive to the potential dangers of awarding a UN oil-for-food contract to Cotecna, a firm that employed his son. And as the report points out, Mr Annan should have made greater efforts to determine the nature of his son's relationship with Cotecna. It is difficult to find fault with the conclusion that, by failing to do so, Mr Annan created a perception of a conflict of interest.

The United Nations must treat the conclusions of Paul Volcker's interim report on the Iraqi oil-for-food programme with the utmost seriousness. The report, by the former chairman of the US Federal Reserve, makes it clear that the conduct of Kofi Annan fell below that expected of someone in his position. The UN secretary general should have been more alive to the potential dangers of awarding a UN oil-for-food contract to Cotecna, a firm that employed his son. And as the report points out, Mr Annan should have made greater efforts to determine the nature of his son's relationship with Cotecna. It is difficult to find fault with the conclusion that, by failing to do so, Mr Annan created a perception of a conflict of interest.

But it is important to maintain a sense of perspective. The secretary general's sin was one of omission, rather than commission. And the report makes it clear that this does not constitute sufficient grounds for his resignation. Furthermore, the real issue is not the behaviour of the secretary general, but the oil-for-food programme itself. Here, the conclusions to be drawn are far less clear cut - and much less convenient for those who will use yesterday's report to renew their calls for Mr Annan's resignation.

The final Volcker report will not be released until the summer, but it is already clear the oil-for-food programme was a deeply flawed mechanism. Allowing Saddam Hussein to choose the middlemen to whom his regime would sell oil was a big mistake. It enabled him to get round the sanctions, imposed since the first Gulf War, by demanding kickbacks in exchange for lucrative contracts. Yet it is important to remember the programme's primary purpose was to prevent the Iraq regime buying arms and materials with which it could threaten its neighbours. As the failure of US weapons inspectors to discover any weapons of mass destruction in Iraq has shown, it was wholly effective in this respect.

It is also worth bearing in mind some stubborn realities about the international trade in oil. The rising price of crude oil since the programme was instituted in 1996 meant that any seller would inevitably be in a position of strength - even one as restricted as Saddam Hussein. And if the programme had not been in place, it is likely that even more barrels would have been smuggled over Iraq's borders.

None of this is to condone the mismanagement of the oil-for-food programme. But it does emphasise the difficulties of policing such a complex sanctions-related mechanism. And the US is arguably just as much to blame as any other nation for the flaws of the scheme. The programme was administered by the United Nations Security Council - on which the US is a permanent member. All the contracts had to be approved by the council's sanctions committee.

This is relevant because the US is by far the most vigorous critic of the UN. And it is American politicians who have made the most strident accusations of corruption. Ever since the UN Security Council refused to back the invasion of Iraq, the Bush administration has seized on every opportunity to discredit the organisation and smear its leader.

It is instructive to trace the course of the way the oil-for-food scandal has emerged. Information was carefully leaked to the US press, that blurred the substantial involvement of US companies and individuals in playing the system. The abuses that emerged, at first, involved mainly companies from France and Russia - two nations that took the lead in opposing the US invasion of Iraq in the Security Council.

The rest of the world must not be swayed by this campaign of vilification. When prominent Republicans called for Mr Annan's resignation last December, the UN ambassadors of 191 countries publicly backed the secretary general. This support is needed more than ever now. John Bolton - who believes "the UN is valuable only when it directly serves the United States" - is soon likely to be approved as the new American ambassador to the organisation. This is no time to concede ground to the world's last remaining superpower in its long struggle to undermine this flawed, but still vitally important, multilateral platform.