Croats have begun casting ballots in an early parliamentary election that is unlikely to produce a clear winner and could pave the way for more political uncertainty in the European Union's newest member state.

Sunday's vote is the second in less than a year. It was called after a previous, right-wing government collapsed after just six months in power, paralyzed by bickering within the ruling coalition.

Opinion polls suggest that neither the conservative Croatian Democratic Union, known as HDZ, nor the left-leaning Social Democrats and their People's Coalition, will win enough votes to rule alone.

This means that some of the smaller groups could play the role of kingmakers, as was the case with the Most group in the previous government.

Croatia has among the weakest economies in the EU.