Bosnia's poll organisers said they hoped parliamentary elections in Bosnian Serb territory would resolve a bitter power struggle between rival leaders.

President Biljana Plavsic, who is backed by the West, and hardline Serb nationalists loyal to the UN-indicted war criminal Radovan Karadzic are struggling for control of the part of Bosnia left in Serb hands after the country's 1992-95 war.

Robert Frowick, the US diplomat who leads the election supervisory effort in Bosnia, said he expected the turnout to be "well over 50 per cent" of the 1.1 million registered voters.

A victory for the hardliners would deliver a humiliating blow to the US-led diplomatic drive to alter the political landscape in Serb territory. It would also allow the hardliners to flout the West's failure to extradite Karadzic to The Hague to stand trial before the UN war crimes tribunal.