change region from Russia to Ukraine

http://www.ilounge.com/index.php/articles/comments/switching-an-itunes-store-acc ount-to-a-different-country/

Depending on the reason why you want to change the region, you might want to create a second Apple ID instead that uses a different region as some apps and content are region specific. Your payment information will also have to be updated to reflect the new region.