"If Croats are not an equal people in Bosnia, the country will be doomed to failure," Covic said at an election rally of the Croatian Democratic Union (HDZ BiH) in Sarajevo.
"Some offer us alms, a republic within the boundaries of western Herzegovina, which is something that the Croat people will never accept," Covic was quoted by the Bosnian issue of the Slobodna Dalmacija daily as saying.
Covic believes that the future of Bosnia lies in government decentralisation and a smaller administrative apparatus.
The international community's High Representative, Paddy Ashdown, said on Tuesday in the town of Siroki Brijeg that in a reorganised Bosnia-Herzegovina municipalities would assume an increasingly important role. He also envisioned a gradual government decentralisation to the benefit of municipal authorities.