While the wording stops well short of an explicit authorisation of force, the resolution sponsored by Britain and France is strengthened by support from Russia, traditionally a friend to Serbia.
President Milosevic's ever- fiercer offensive against the ethnic Albanian population in Kosovo has left an estimated 50,000 refugees without food and shelter as the first snows of winter fell last week. Hundreds have died since the fighting stepped up in February.
The Foreign Secretary, Robin Cook, said the resolution passed by a 14- 0 vote showed the international community had run out of patience.
Mr Cook said: "There must now be a ceasefire and rapid progress on a political dialogue, which is the only route to a lasting solution to the humanitarian problem."
Nato planners are starting to line up contributions to a force that would carry out contingency plans to attack Yugoslav military targets in Kosovo and failing that, the rest of Serbia.
Today Nato ambassadors in Brussels will give the go-ahead for assembly of a force, before alliance defence ministers give a public imprimatur at their regular autumn talks at Vilamoura in Portugal. Germany has promised 14 Tornado aircraft, while the Netherlands has reportedly pledged a squadron of F-16 fighters.
The apparent new-found determination to get to grips with what is already a colossal humanitarian disaster came as Serb forces continued to pound Kosovo's central Drenica region, stronghold of the secessionist Kosovo Liberation Army (KLA). Serb units captured and set fire to more than a dozen villages, putting to flight a further 20,000 Albanian civilians.
In the past, this sort of ultimatum has been blithely ignored by President Milosevic. But this time, Nato members are only too well aware that the last shreds of their credibility in Kosovo are on the line, and they have perhaps their last chance to make good on the repeated undertaking that, come what may, they would never permit another Bosnia.
Instead, events are unfolding in ominously similar fashion. An estimated 300,000 now homeless, a humanitarian crisis this winter is already assured.
Evidence is growing too of atrocities, with assurances from Belgrade that the situation had been "stabilised" and that refugees were now returning to their homes.
United States officials at Nato have given an unusually detailed idea of what form the strikes could take, suggesting that they could start with cruise missile attacks against Serb communications facilities and depots in Kosovo.Reuse content