The details were given by military spokesman Colonel Konrad Freytag at Nato's daily briefing in Brussels.

He did not break the figure down into dead and wounded, but Nato sources say they believe more than 5,000 Yugoslav soldiers have been killed since 24 March.

Belgrade has given little public information on military casualties.

The Yugoslav army announced on Tuesday that the air force Deputy Chief of Staff, General Ljubisa Velickovic, had been killed while inspecting units in "the first line of defence".

Two days ago the commander of Yugoslav forces in Kosovo talked about their losses there being less than 1%. Correspondents say this would suggest fewer than 1,800.

General Velickovic: Killed while "inspecting units"

"But our estimate is much higher," Col Freytag said. "Losses and injured people is far more than 10,000."

Col Freytag said fresh Serb forces had been seen bringing in "more modern equipment" including tanks. "So the battle is not over yet," he added.

Nato operations in Kosovo have continued, with attacks for the third day running on Serb forces mounting counter-offensives in the south-west against the separatist Kosovo Liberation Army, around Mount Pastrik.