The Sunday Times quotes an unnamed source as saying that the need for medical staff will be great once Nato forces enter the troubled province.

But a statement from the Ministry of Defence dismissed the report.

A spokesman said: "We have 12,000 regular army personnel prepared to join Nato ground forces - but no current plans to call up any reservists."

'Largest call-up since Suez'

Medics who have served in the military in the last 10 years or who are in the Territorial Army can be compelled to leave their civilian jobs.

The Sunday Times' source said: "By the time we enter Kosovo we will find no local medical facilities and hordes of local people on the point of dying."

The newspaper reports that the call-up would be the largest since the 1957 Suez crisis.

Meanwhile, the Ministry of Defence has also denied reports in the Sunday Telegraph that Defence Secretary George Robertson had offered to supply 50,000 British troops towards a 150,000-strong Kosovo invasion force.

The offer was said to have been made at an unpublicised meeting in Bonn on Thursday between Mr Robertson, US Defence Secretary William Cohen and their French, German and Italian counterparts.

But Foreign Secretary Robin Cook echoed an earlier denial from an MoD spokesman that Nato had not taken any decision on a ground invasion force for Kosovo.

'No decisions'

Mr Cook said: "We are not making any decisions at the present time, nor is there a proposal in front of us to make a decision, but we have always said all options are under review."

He said the air campaign was having an increasing impact on the Serb and Yugoslav forces deployed in Kosovo.