The rejection of the changes is likely to halt the entire process of constitutional reforms.
In the 42-seat House of Representatives, 26 members voted for the draft changes, but the adoption of the bill required a two-third majority, i.e. 28 votes in favour.
The changes, which seven major political parties recently agreed on at the insistence of the international community, were turned down in the parliament due to the strong opposition of Croat deputies from the newly-established HDZ 1990 party and the Party of Bosnia-Herzegovina led by a former Bosnian foreign minster, Haris Silajdzic.
The ambassadors of the United States and the European Union in Sarajevo who attended the session expressed disappointment at the outcome of the voting.
On Tuesday, at the start of the discussion on this topic the chairman of Bosnia's three-man presidency, Sulejman Tihic, expounded the draft amendments saying that they would help Bosnia to be organised as a more efficient and cost-effective state, more capable of addressing the challenges stemming from the country's efforts to join Euro-Atlantic integration processes. Tihic told parliament that the institution of the President of Bosnia-Herzegovina would be established and that the role of the current Council of Ministers (the government) would be expanded and strengthened.
"I am convinced that these solutions are good for Serbs, for Bosniaks and for Croats," Tihic said, commenting on the position of the three constituent peoples.
The opponents said that the changes cemented the division of the country into the two entities and retained mechanisms of voting according to the entity model.
In addition, the Bosnian Croat political leadership has been divided into the bloc for and the bloc against the changes. The latter fears that the amendments will produce adverse effects on the Croat community.