What term was used by Winston Churchill in 1946 to describe the spread of communist control across Europe?

Churchill referred to the domination of eastern Europe as the descent of an Iron Curtain between those countries and the West, and the name became a popular term to describe the dividing line between the democracies and Soviet puppet states.

The text of Churchill's remarks (March 5, 1946) :

"From Stettin in the Baltic to Trieste in the Adriatic, an iron curtain has descended across the Continent. Behind that line lie all the capitals of the ancient states of Central and Eastern Europe. Warsaw, Berlin, Prague, Vienna, Budapest, Belgrade, Bucharest and Sofia, all these famous cities and the populations around them lie in what I must call the Soviet sphere, and all are subject in one form or another, not only to Soviet influence but to a very high and, in many cases, increasing measure of control from Moscow. "