What is Niko's nationality in GTA 4?

Given his European origins, some GTA 4 players remain confused about Niko Bellic’s nationality.

Niko Bellic - Grand Theft Wiki, the GTA wiki

Roman Bellic GTA+BreezeWiki

Niko Bellic GTA+BreezeWiki

Main Characters - GTA 4 / Grand Theft Auto IV - on

Niko Bellic, Rockstar Games Wiki

Official GTA4 Website Launch! –

Mikhail Faustin - Grand Theft Wiki, the GTA wiki

Niko Bellic, The Grand Theft Auto IV Chain Story Wiki

Darko Brevic GTA 4 Characters, Bio & Voice Actor (GTA IV, TLaD & TBoGT)