SARAJEVO, Bosnia-Herzegovina—The Bosnian prosecutor's office said Wednesday it is investigating who is at fault after the European Union halved the country's funding because its squabbling leaders haven't changed the constitution to allow more rights for minorities.

The EU announced it would cut funding this year by 45 million euros ($62 million) because of a lack of action on a ruling by the European Court of Human Rights that Bosnia must amend its constitution.

The statement from the prosecution office said by trying to pinpoint the culprits, it is acting in the interest of Bosnia's citizens since the lack of implementation of the European human rights court's ruling "inflicts significant harm" to Bosnia's efforts to become an EU member and deprives its citizens of badly needed EU funds.

Bosnia's constitution is part of the peace agreement that ended the 1992-95 war. It divided the country in two fairly autonomous regions, linked by a central government. It also installed a power-sharing system between the country's three main ethnic groups—Bosniaks, Serbs and Croats—effectively excluding minorities from leadership.

Then, a Roma and a Jew sued the country in the EU court and won. The court ordered Bosnia to remove the discrimination from its constitution, but politicians have argued for four years over how to do that.

The negotiations failed because Bosnian Croats condition their approval of the constitutional changes with additional alterations that would guarantee them the exclusive right to elect their representative in Bosnia's three-member presidency.

Croats are formally one of the three currently privileged ethnic groups that share power in Bosnia. But numerically they are a minority compared to the Bosniaks in the half of the country the two groups share.

In the 2006 elections, an ethnic Croat from a mixed party won the elections for the Croat seat in the presidency because more Bosniaks voted for him than for their own ethnic representative.

Meanwhile, all other countries in the region are getting closer to EU membership while Bosnia is running in circles and could face more sanctions from the Council of Europe—even a suspension of membership.