Croatia's Foreign Minister, Mate Granic, said that Mr Carter's mission could be counted as a limited success if a ceasefire actually took hold in Bosnia. However, in a reference to the Bosnian Serb leader, Radovan Karadzic, Mr Granic added: "In view of previous experiences with Karadzic and his promises, one will have to remain very careful."
Not every verdict on Mr Carter's mission on Monday and Tuesday was negative. The UN Secretary-General, Boutros Boutros-Ghali, said: "What has been achieved by Carter has created a new momentum. What's important now is how to fulfil this momentum. The ce a sefire will help us to begin new negotiations." In the view of Western governments and leaders of Bosnia's Muslim-Croat federation, the problem is that a new set of negotiations risks unravelling everything that has been agreed up to now.
The plan devised by the US, Russia, Britain, France and Germany envisages giving the federation 51 per cent of Bosnia and the Bosnian Serbs 49 per cent. Apart from the Bosnian Serbs, it has been accepted by all parties linked with the conflict, includin g Serbia.
For months, the Bosnian Serb leadership has been looking for a way out of its isolation so that Bosnia's partition can be tackled afresh without using the 51:49 per cent formula as a basis for negotiations. Mr Carter's trips to Sarajevo and Pale, the Bosnian Serb headquarters, appear to have provided them with just that opportunity.
The Bosnian Serbs now say they will restart talks with the 51:49 per cent plan as a "starting point", not a "basis", for dividing Bosnia. What they have in mind was spelt out in a memorandum submitted to Mr Carter by Mr Karadzic this week.
First, the Bosnian Serb leader revived his long-standing demand for Sarajevo to be split into a Serbian and a Muslim sector. This is quite contrary to the terms of the Western-Russian peace plan and makes plain the Bosnian Serbs' objective of burying theidea of a united Bosnia with Sarajevo as its capital.
Second, he demanded access to the Adriatic Sea for the self-styled Bosnian Serb state. This is a Serbian ambition dating back to the 19th century and is unacceptable to Muslims and Croats who suspect it is aimed at permanently weakening Bosnia and Croatia.
In his third and fourth points, Mr Karadzic asked for the equal distribution of Bosnia's resources and infrastructure between the Bosnian Serbs and the Muslim-Croat federation, and said both areas should be economically viable. He argued that the international plan discriminated against his people by awarding them only 30 per cent of Bosnia's wealth.
Finally, Mr Karadzic appealed for "natural and defensible" frontiers for the Bosnian Serb area.
This implies not merely a redrawing of Bosnia's internal borders, as envisaged in the five-nation plan, but the establishment of a Bosnian Serb state irreversibly separated from the rest of Bosnia.
At least in public, Western countries have never accepted that Bosnia can be partitioned in so final a manner.
As far as the planned "Christmas ceasefire" goes, there is more to it than meets the eye. The Bosnian Serbs have reserved the right to discontinue the ceasefire after 1 January if there is no agreement on a "total cessation of hostilities" by then.
Such a cessation would suit the Bosnian Serbs by freezing battle fronts in their favour. But if fighting resumes after 1 January, they have still done their image in the West some good by not making war over a holiday period.
Of course, since neither the Orthodox Serbs nor the Muslims celebrate 25 December, it could be argued that all the talk of a "Christmas ceasefire" is mere humbug designed for Western consumption.