Bülent,
It depends which federation or association your dojo is part of, not so much which country you live in (though I imagine some countries only have one federation/association, but those are rare, no?).
http://www.aikiweb.com/general/affiliat.html shows just how vast the Aikido world is. It would be interesting to know which ones have colored belts, hakama before Shodan (i.e. ASU), no hakama ever, etc...