The long-delayed genocide trial of Momcilo Krajisnik, once the second most powerful Serb politician in Bosnia, opened Tuesday with the prosecutor claiming the ex-legislator helped craft the brutal wartime policy of ethnic cleansing. Krajisnik was "fully aware of the horrific consequences," Mark Harmon, the U.N. prosecutor, said in an opening statement at the trial in The Hague. Krajisnik, 59, was head of parliament and the right-hand man of Bosnian Serb President Radovan Karadzic during the 1991-1995 Bosnian war, which left at least 250,000 Muslims dead. His trial at the U.N. war crimes tribunal is seen as one of the most critical for establishing political blame for atrocities committed by Bosnian Serb troops. Krajisnik pleaded innocent to eight counts of war crimes, including genocide and complicity in genocide. Previously, he said the indictment was too vague to be credible, and claimed the court had no jurisdiction to hear his case. In a departure from normal procedure, Krajisnik asked the court to be allowed to give his own opening statement. The tribunal said it would rule later on the request. He sat calmly taking notes as Harmon laid out the case against him. "Along with Radovan Karadzic, it was his hand that held firmly the levers of power," said Harmon. Together with Karadzic and the tribunal's most prominent suspect, Slobodan Milosevic, Krajisnik "was vital for developing and promoting ethnocentric policies," Harmon said. "He was fully aware of the horrific consequences their implementation would visit on non-Serbs in Bosnia and Hertzegovina and he was indifferent," said the prosecutor. Harmon said Krajisnik was a "shrewd and calculating man, a committed and unrepentant Serb nationalist" who bears responsibility for the deaths of thousands of innocent Bosnian Muslims and Croats. Krajisnik, a former businessman, co-founded the Serb nationalist party in Bosnia with Karadzic and became speaker of the Bosnian parliament in 1990, before Serbs walked out and the war began. Later, he was one of the negotiators of the Dayton peace accords which ended the war, although foreign mediators dubbed him "Mister No" for his stubbornness. Karadzic is now the tribunal's most wanted fugitive, along with the top Bosnian Serb military commander, General Ratko Mladic. After the war ended in 1995 Krajisnik continued to advocate independence for Bosnian Serbs, but he served as the first Serb representative on the three-member Bosnian presidency, along with a Croat and a Muslim. Krajisnik was arrested at his home in Pale in April 2000 during an early morning raid by French NATO troops, who blasted off his door with explosives and led him away in pajamas. He was indicted together with the former Bosnian president, "Iron Lady" Biljana Plavsic, on nearly identical charges. Plavsic surrendered voluntarily. **PHOTO CAPTION*** Momcilo Krajisnik, seen here (R) at an earlier appearance, (AFP/Pool/File/Serge Ligtenberg)