The efforts were initially focused on the peaceful use of atomic energy; Soviet-North Korean agreements of the time specifically emphasized the peaceful nature of bilateral cooperation in the nuclear sphere. An intergovermental agreement on cooperation in the field of atomic energy, signed in 1959, laid the foundation for joint nuclear activities between the Soviet Union and North Korea.
Brezhnev was pushed by North Korea to expand their assistance for nuclear energy to allow North Korea a broader scale operation which would make them capacle of building nuclear weaponry. Brezhnev declined further assistance for fear that North Korea would create nuclear warheads and use them.
The years of delays and stall tactics by Russia and other countries significantly delayed North Korea from getting nuclear warheads for decades. Now however, it appears they may have taken the nuclear energy program Brezhnev assisted them with and advanced their capability into creating a nuclear warhead.
For more information on the present crisis go to: http://www.cnn.com/2013/04/11/world/asia/koreas-tensions/index.html
This cloud of the side of Brezhnev's face appeared in the sky several days ago in Connecticut. The incomplete blue heart shaped around Brezhnev's face parallels the incomplete nuclear capability that Breszhnev insisted on to protect the world from a Nuclear North Korea.
Brezhnev's side silhouette is on the right side inside the blue outlined heart.