EU citizens need a visa to enter Belarus.
Until December 31, 2007 Russian visa entitled its bearer to stay on the territory of Belarus for 48 hours on the way to Russia and 48 hours on the way back. At present, a separate Belarusian transit visa is required.
Standard cost of Belarusian tourist visa is 25 EUR .
Cost of transit visas: 10 EUR  (single), 15 EUR  (double).
See also: Tourist agencies