I want to know the answer to the following question:
What country was afforded access to design of improved nuclear weapon through espionage?
All the background I'm provided with is that "He then collaborated with Klaus Fuchs on further development of the bomb, and in 1946 the two filed a secret patent on "Improvement in Methods and Means for Utilizing Nuclear Energy", which outlined a scheme for using a fission bomb to compress fusion fuel to initiate nuclear fusion.". Is that enough to answer the question?