But it said that it was planning a study to "assess whether there has been an increased rate of cancer amongst military personnel, who served in the Gulf War or Balkans, as well as amongst exposed populations". It also called for cordoning off and cleaning up sites in Kosovo, where depleted uranium (DU) ammunition landed during the NATO air campaign.

Future research would include assessing links between exposure to uranium and kidney damage, and studies of the "reproductive, mutagenic and carcinogenic properties of uranium".

Italy recently demanded that NATO investigate whether the deaths of six of its soldiers from leukaemia, after tours of duty in Kosovo and Bosnia was due to the so-called "Balkans Syndrome". "Given the remaining uncertainties about the effects of DU, it seems reasonable to undertake clean-up operations, in impact zones where there are substantial numbers of radioactive particles remaining," WHO said.

"If there are very high concentrations of DU, then areas may need to be cordoned off, until the particles are removed. This is especially the case where children are likely to be present."

On Thursday, Mr Klaus Toepfer, head of the UN Environment Programme, and Pekka Haavisto, who leads its Balkans Task Force team, which has collected samples at 11 sites in Kosovo, said all 112 Kosovo sites should be analysed for possible health risks.

(Reuters)