The Croatian attack on Serb positions north of Dubrovnik and Bosnian Croat advances in western Bosnia around the town of Drvar appeared to have been put on hold yesterday, although the Dubrovnik operation may only have been postponed.
"Our assessment is that they are battle-ready and could strike at any time", said Major Don Roy, a UN military spokesman.
It looks as if a desire to give the new US peace plan a chance, possibly combined with caution about Serb defensive measures in the area, induced the Croats to hold back.
There has also been direct pressure on Croatia from the United States, which lent tacit support to the Croats' recapture of Krajina, not to continue attacks on the Serbs. However, a senior western diplomat said, "one cannot conclude the operation is off".
While all seemed quiet on the Croatian and Bosnian Croat fronts, Serb shells rained into Sarajevo, the worst shelling for two weeks, killing four people and injuring at least 29, including six Egyptian UN peacekeepers and two children.
A five-storey apartment block was hit, apparently by a rocket, demolishing four floors and setting it on fire. The building was largely empty, but one woman was injured. Witnesses said they saw explosions from ammunition stored in one of the flats. The six Egyptians were wounded when their position was deliberately fired on by Bosnian Serb mortars. The UN in Sarajevo said it had been unable to locate the mortar, and under the rules of engagement, could not return fire.
Last week the Croatian army moved at least 4,000 troops from Split into the Dubrovnik area, apparently poised to move north to Trebinje to drive Serb artillery out of range of the medieval city. Some reports suggest as many as 10,000 troops have been deployed, although British sources believe this is an exaggeration.
The Croats had been riding a wave of success following their unexpectedly swift seizure of the Serb-held Krajina and the flight of most of the population, and the Bosnian Croats' unexpected success in surrounding Drvar, although there has been no confirmation that the Bosnian Serb town has fallen.
"If I was them I'd have gone for it", a British military source said. "If they take Trebinje and there's a peace plan they'd be in the driving seat."
Carl Gorisek, a retired Croatian general, said he thought Croatia did not want to "muddy the water" or jeopardise the new US peace initiative, especially following the death of senior US representatives in a road crash on the way to Sarajevo at the weekend. Another Croatian analyst, Fran Visnar, speaking of the situation around Dubrovnik, said: "Croatia is likely to show patience now in order not to jeopardise the new American peace initiative and avert a wider war. A diplomatic solution would entail creating a demilitarised zone and pulling back long-range artillery on both sides".
While Croatia appears to be co-operating with the US, the UN Rapid Reaction Force has continued to encounter obstruction from the Croats, Bosnian Croats and the Bosnian government. Yesterday four of the eight self-propelled guns were reported to have reached Mt Igman to join 12 British 105mm guns supposedly guarding the mountain road. The other four were still held up on the border but the UN hoped they would be allowed through.