With a consensus that the international community must not give the Yugoslav president immunity from prosecution, the alliance is discussing other possibilities if it has to deal with him. Asked about his fate, one senior diplomat said that "there are countries around the world that can give haven".
The consideration being given to the future of President Milosevic reflects growing confidence that the bombing campaign will yield results in eight weeks, producing the environment for an endgame.
Some of the alliance's most senior figures believe that the Yugoslav leader may be swept from power by popular dissent. This is the "Ceausescu scenario", referring to the Romanian dictator shot dead in December 1989. Another scenario would see him ousted by his inner circle. But with no clear sign of either of these emerging, another diplomat recalled the fate of Idi Amin, who was offered sanctuary abroad to hasten the end of his bloody regime in Uganda.
Such an outcome would anger many human rights activists who want Mr Milosevic to face trial not only for ethnic cleansing in Kosovo but also for earlier atrocities in Bosnia.
However diplomats say it would be preferable to him continuing in power. With President Milosevic likely to demand immunity in any negotiations, an agreed haven for him and his family is seen as a possible solution that might assist a deal that avoids the need for Nato troops to fight their way into Kosovo.
Yesterday the alliance spokesman, Peter Daniel, refused to say whether the alliance would negotiate with President Milosevic, or who would sign an eventual agreement, but he added: "At the end of the day an agreement takes two. There will be one party, Nato, and the other, the Federal Republic of Yugoslavia."
There was no mention of which state the Serb leader would be most likely to find refuge in. One possibility is Belarus. An Orthodox Slav state, the leadership of the former Soviet republic shares President Milosevic's antipathy to all things Western and, above all, to Nato.