I'd forgotten all about urban areas! How many cities are you looking to restrict it to?
Five cities: Minsk, Kiev, Smolensk, Kursk, Kharkov.
Four cities: Minsk, Kiev, Smolensk, large Kursk & Kharkov combined.
Three: Minsk & Smolensk, Kiev, Kursk & Kharkov.
Two: Minsk & Smolensk, Kiev & Kursk &...