Just fourteen months ago, on a bleak, frosty afternoon, I stopped my car beside an old Ottoman bridge in southern Kosovo. It was here, scarcely half a year earlier, that Nato jets had bombed a convoy of Albanian refugees, ripping scores of them to pieces in the surrounding fields. Their jets, I knew, had been firing depleted uranium rounds. And now, on the very spot east of Djakovica where a bomb had torn apart an entire refugee family in a tractor, five Italian Kfor soldiers had built a little checkpoint. Indeed, their armoured vehicle was actually standing on part of the crater in the road.

I tried to warn them that I thought the crater might be contaminated. I told them about depleted uranium and the cancers that had blossomed among the children of Iraq who had - or whose parents had - been close to DU explosions. One of the young soldiers laughed at me. He'd heard the stories, he said. But Nato had assured its troops that there was no danger from depleted uranium. I begged to differ. "Don't worry about us," the soldier replied.

They should have known better. Only a few weeks earlier, a team of UN scientists - sent to Kosovo under the set of UN resolutions that brought Kfor into the province - had demanded to know from Nato the location of DU bombings in Kosovo. Nato refused to tell them. Nor was I surprised. From the very start of the alliance bombing campaign against Serbia, Nato had lied about depleted uranium. Just as the American and British governments still lie about its effects in southern Iraq during the 1991 Gulf War. US and British tanks had fired hundreds of rounds - thousands in the case of the Americans - at Iraqi vehicles, using shells whose depleted uranium punches through heavy armour and then releases an irradiated aerosol spray.

In the aftermath of that war, I revisited the old battlefields around the Iraqi city of Basra. Each time, I came across terrifying new cancers among those who lived there. Babies were being born with no arms or no noses or no eyes. Children were bleeding internally or suddenly developing grotesque tumours. UN sanctions, needless to say, were delaying medicines from reaching these poor wretches. Then I found Iraqi soldiers who seemed to be dying of the same "Gulf War syndrome" that was already being identified among thousands of US and British troops.

At the time, The Independent was alone in publicising this sinister new weapon and its apparent effects. Government ministers laughed the reports off. One replied to Independent readers who drew the Ministry of Defence's attention to my articles that, despite my investigations, he had seen no "epidemiological data" proving them true. And of course there was none. Because the World Health Organisation, invited by Iraq to start research into the cancers, was dissuaded from doing so even though it had sent an initial team to Baghdad to start work. And because a group of Royal Society scientists told by the British authorities to investigate the effects of DU declined to visit Iraq.

Documents that proved the contrary were dismissed as "anecdotal". A US military report detailing the health risks of DU and urging suppression of this information was dutifully ignored. When two years ago I wrote about a British government report detailing the extraordinary lengths to which the authorities went at DU shell test-firing ranges in the UK - the shells are fired into a tunnel in Cumbria and the resulting dust sealed into concrete containers which are buried - I know for a fact that the first reaction from one civil servant was to ask whether I might be prosecuted for revealing this.

One ex-serviceman, sick since the Gulf War, actually had his house raided by the British police in an attempt to track down "secret" documents. More honourable policemen might have searched for papers that proved DU's dangers - and which might form the basis of manslaughter charges against senior officers. But of course the police were trying to find the source of the leak, not the source of dying men's cancers.

During the Kosovo war, I travelled from Belgrade to Brussels to ask about Nato's use of depleted uranium. Luftwaffe General Jerz informed me that it was "harmless" and was found in trees, earth and mountains. It was a lie. Only uranium - not the depleted variety that comes from nuclear waste (that is concentrated) - is found in the earth. James Shea, Nato's spokesman, quoted a Rand Corporation report that supposedly proved DU was not harmful, knowing full well - since Mr Shea is a careful reader and not a stupid man - that the Rand report deals with dust in uranium mines, not the irradiated spray from DU weapons.

And so it went on. Back in Kosovo, I was told privately by British officers that the Americans had used so much DU in the war against Serbia that they had no idea how many locations were contaminated. When I tracked down the survivors of the Albanian refugee convoy, one of them was suffering kidney pains. Despite a promise by Shea that the attack would be fully investigated, not a single Nato officer had bothered to talk to a survivor. Nor have they since. A year ago, I noted in The Independent that foreign secretary Robin Cook had admitted in the House of Commons that Nato was refusing to give DU locations to the UN. "Why?" I asked in the paper. "Why cannot we be told where these rounds were fired?"

During the war, defence correspondents - the BBC's Mark Laity prominent among them - bought the Nato line that DU was harmless. Laity was still peddling the same nonsense at an Edinburgh Festival journalists' conference some months later. Laity - who is now, of course, an official spokesman for Nato - was last week reduced to saying that "the overwhelming consensus of medical information" is that health risks from DU are "very low". But the growing consensus of medical information is quite the opposite. Which is why a British report to the UK embassy in Kuwait referred to the "sensitivity" of DU because of its health risks.

And still the Americans and the British try to fool us. The Americans are now brazenly announcing that their troops in Kosovo have suffered no resultant leukemias - failing to mention that most of their soldiers are cooped up in a massive base (Fort Bondsteel) near the Macedonian border where no DU rounds were fired by Nato. Needless to say, there was also no mention of the tens of thousands of US troops - women as well as men - who believe they were contaminated by DU in the Gulf.

So it goes on. British veterans are dying of unexplained cancers from the Gulf. So are US veterans. Nato troops from Bosnia and now Kosovo - especially Italians - are dying from unexplained cancers. So are the children in the Basra hospitals, along with their parents and uncles and aunts. Cancers have now been found among Iraqi refugees in Iran who were caught in Allied fire on the roads north of Kuwait. Bosnian authorities investigating an increase in cancers can get no information from Nato. This is not a scandal. It is an outrage.

Had we but known. On those very same Iraqi roads, I too prowled through the contaminated wreckage of Iraqi armour in 1991. And - I recall with growing unease - back in Kosovo in 1999, only a day after the original attack, I collected pieces of the air-fired rounds that hit the Albanian refugee convoy. Their computer codes proved Nato had bombed the convoy - not the Serbs, as Nato tried to claim. I also remember that I carried those bits of munition back to Belgrade - in my pocket. There are times, I must admit, when I would like to believe Nato's lies.