Resort city in the Crimea, where Stalin, Roosevelt and Churchill conferred in February 1945 (5)
I believe the answer is:
yalta
(Other definitions for yalta that I've seen before include "Black Sea resort" , "Ukrainian resort" , "City on the Black Sea, where Roosevelt, Stalin and Churchill met in 1945" , "Site of the Allied conference in 1945" , "Churchill, Roosevelt and Stalin met here in nineteen forty five" .)