Complex sentence: The issue was raised by official visits by Norwegian politicians to the Soviet Union in 1966,1967 and 1968, and in 1968, the Soviet Consul in Barentsburg again visited Ny-Ålesund and attempted to make inspections of the installation.
Split into simpler sentences: The issue was raised at official visits to the Soviet Union by Norwegian politicians in 1966,1967 and 1968. The Soviet Consul in Barentsburg visited Ny-Ålesund in 1968 and attempted to make inspections of the installation.