Mr Hurd and his French counterpart, Alain Juppe, toured the region to persuade Mr Milosevic and the warring factions in Bosnia that the Geneva plan, which calls for the Bosnian Serbs to surrender 30 per cent of the land they hold to the Sarajevo government, is a last chance for peace.
Despite what Mr Hurd described as 'very frank' talks with Mr Milosevic and the Bosnian Serb leader, Radovan Karadzic, the ministers received no definite answer in Pale, capital of the self- styled Bosnian Serb republic, or in Belgrade.
The two ministers warned of intensified war in Bosnia, even throughout the Balkans, if the plan is rejected. But the sticks they bear - threats to lift the arms embargo on the Muslim-led Bosnian government if the Serbs say no, or to lift sanctions on Serbia if Sarajevo says no - have so far failed to push either side towards peace.
Many United Nations officials and diplomats expect a conditional yes, tying the hands of the international community and paving the way for protracted negotiations and continued fighting in Bosnia. Russia and the West have emphasised the 'take it or leave it' nature of the peace proposal.
'We have asked for clear-cut answers on 20 July,' said Charles Redman, the United States envoy. 'We certainly hope there will be no buts.' It may prove a forlorn hope. President Alia Izetbegovic said yesterday that his government would accept 'a bad plan' under one condition: 'Bosnia-Herzegovina must continue to exist within the internationally recognised borders and its integrity and sovereignty must be acknowledged.'
Mr Hurd reassured him, saying: 'It is not a plan of partition' but one which 'provides for the integrity of those borders with constitutional arrangements which can be revised by agreement'. Mr Karadzic was scathing. 'I cannot think why anyone should put us together to live in the same state as our enemies,' he said in Pale.
He added that the Serbian response would follow on Monday, when the Bosnian Serb assembly (and its counterpart in Sarajevo) meets to consider the proposal.
Mr Juppe told reporters: 'A refusal by the Bosnian Serbs would isolate them completely from the international community.' The Pale leadership already risks alienating Mr Milosevic.
The offical Belgrade media has urged acceptance of the plan, to ensure the lifting of the economic embargo against Serbia. There have been veiled threats in the Serbian press to identify unnamed Bosnian Serb leaders allegedly implicated in corruption scandals. But Pale has defied Belgrade before, most importantly when it rejected the Vance-Owen plan last year. It will be reluctant, however strong the diplomatic pressure, to surrender a third of its gains made on the battlefield.
'The war that started in the former Bosnia-Herzegovina must end here', said General Manojlo Milovanovic, a senior Bosnian Serb commander. 'The war will not end in Geneva, London or New York.'
These sentiments are shared by many Bosnian generals, who are starting to enjoy the fruits of the Washington agreement between Bosnia and Croatia. Weapons are being smuggled in from Croatia in defiance of the arms ban. Recently, the Bosnian army has taken the fight to its Serbian enemy for the first time. Although it has yet to make - and hold - significant gains, the Bosnian military may believe it can achieve more through war than talks.