Britain is poised to order the dispatch of 5,000 more troops to the Balkans this week as NATO seeks agreement on an expanded Kosovo peacekeeping force without reopening bitter divisions over a ground invasion.
Whitehall sources said last night that the British Prime Minister, Mr Tony Blair, and senior ministers could approve the decision as soon as Thursday following moves in Brussels to authorise a "K-For Plus" of 45,000 to 48,000 troops to enter the province once Yugoslav forces have withdrawn or are starting to retreat.
Britain's new contribution will add up to a total UK presence of some 13,000 soldiers, an increase seen as necessary because NATO requires a substantially larger force than the 28,000-strong force originally planned to implement the Rambouillet agreement.
More troops are now needed to deal with large-scale reconstruction, mine-clearing, engineering work and residual resistance, even in the event - unlikely at the moment - of Belgrade agreeing to a NATO-led deployment.
Publishing what it said was a leaked draft of the revised K-For plan, the Greek daily Kathimerini said the takeover of the province was code-named Operation Joint Guardian, and that NATO is warning that one of the most difficult tasks will be the disarming of the Kosovo Liberation Army.
Kathimerini said the NATO-led force would be "the only authority" controlling Kosovo's airspace and that in the updated plan "a non-NATO authority" was proposed to supervise Yugoslavia's airspace. It suggested three zones (including a no-fly zone and a zone controlled south of the 44th parallel) be created.
It also proposed a "green line" between the borders of Kosovo, Serbia and Montenegro as well as a 25km-wide "security" zone between Kosovo and Macedonia.
However, the British Foreign Secretary, Mr Robin Cook, who spent two days in Washington last week trying to resolve embarrassing Anglo-American differences on the ground troops issue, made it clear yesterday that K-For was not intended to fight its way in against organised opposition.
Mr Cook also signalled that more robust options were being explored. He pointed to US support for NATO to update planning for ground troops in either a "permissive or non-permissive environment".
K-For would not have the armoured punch of an invasion force, which could number more than 150,000, but it could clearly provide the core for one if the bombing failed to force a climbdown and the mood in NATO changed.
"In the next two to three weeks we need a political breakthrough on a peace resolution," said a veteran NATO diplomat. "If not, some tough choices on ground forces will have to be made."
Italy's Foreign Minister, Mr Lamberto Dini, said yesterday that he did not foresee a swift end to the Kosovo crisis. "We should not think of an intervention by ground troops but must work to arrive at a negotiated solution," he said.
The West's most senior peace envoy in Bosnia, Mr Carlos Westendorp, said ground troops had to be sent in. "I think that if we don't send ground troops this conflict will never be resolved," he said.
In Washington President Clinton used an article in the New York Times to insist that NATO air strikes were working, although in a distinct nod to Mr Blair he added that he did not rule out "other military options". K-For, Mr Clinton said, "must have NATO at its core".