That's interesting. Even if the volume was low, perhaps the Russians were nevertheless interested in sowing dissent in the German public opinion. In particular, making sure the energy sector is always dependent on some foreign source.
That plus well developed civilian nuclear power gives the means to developing atomic bombs, and Russia has every reason to fear a nuclear-armed Germany
I doubt that this was a major concern as US nuclear weapons have been stationed in Germany since 1960. They remain under US control but the German army is trained to use them in the event of a war. And of course Soviet nuclear weapons used to be stationed in East Germany during the cold war. So for practical purposes Germany was already nuclear-armed.
But who knows. This was 15 years after the end of WW2. It wouldn't be too surprising if there had been lingering fears in Russia about what Germany might be up to outside of NATO.
