A meeting of Mr Silajdzic, the Bosnian President, Alija Izetbegovic, and the US Assistant Secretary of State, Richard Holbrooke, highlighted the Sarajevo government's frustration over what it perceives as a weakening of support from its key ally.
Yesterday's disagreement made it unlikely that any progress could be made quickly on a political settlement of the 33-month-old war.
Mr Holbrooke said the five-nation Contact Group - representatives of the US, Russia, Britain, France and Germany - would begin a new round of talks tomorrow in an attempt to reach a final political settlement.
The Contact Group has proposed giving Bosnian Serbs, who hold 70 per cent of the republic, 49 per cent. The government and its Croat allies would get 51 per cent. The government accepted the non-negotiable plan, but the Bosnian Serbs have rejected it.
Mr Holbrooke said the Contact Group is trying to get its plan accepted "as a starting point for negotiations, and we believe this is vitally important now that a ceasefire and cessation of hostilities are essentially in place".
There has been no change in the plan, he said. "That's your position, Mr Holbrooke," interrupted Mr Silajdzic angrily, adding that the plan had become "a bit unfair".
"We accepted the plan with no conditions," he said. "Now the position has shifted a little bit when it comes to the aggressor."
The US has been the Bosnian government's biggest backer. But the Clinton administration finds itself trying to bring the Serbs back to the bargaining table while fending off an attempt by the Senate majority leader, Republican Robert Dole, to lift an embargo and arm the Bosnian government.Reuse content