In their Vienna summit meeting in June 1961, Khrushchev and Kennedy both reached an informal understanding against nuclear testing, but the Soviet Union began testing nuclear weapons that September.
Dalam pertemuan Wina Juni 1961, Khrushchev dan Kennedy membuat persetujuan informal melawan pengujian nuklir, tetapi Uni Soviet mulai menguji senjata nuklirnya September itu juga.