UN General Assembly
1963

6. It is said, of course, that underground testing demands much greater skill and experience than other nuclear tests; but, with the growing number of nuclear scientists in many countries and the constantly developing use of nuclear energy for peaceful purposes, I greatly fear that before long additional States will be technically capable of producing nuclear weapons without testing them in the atmosphere —or perhaps even without testing them at all. 7. However, though the Moscow Treaty may not have entirely precluded the possibility of further Powers developing nuclear weapons, surely it justifies and encourages the continuance of all possible efforts in that direction. We sincerely hope, therefore, that this initial tripartite success in obtaining a limited agreement in the nuclear field will spur the four Powers concerned to use every possible endeavour to secure the conclusion —before it is too late— of the basic agreement to stop once and for all any further spread of nuclear weapons.