While reading a bit and looking a bit over the Apartheid wiki I learned about how horrible the Swiss apparently were like holy shit:

Among the study's revelations is the finding that Swiss industry got around the UN arms embargo in grand style.
Swiss industry even violated rules on arms exports defined by Switzerland, although they were interpreted far more narrowly than those of the UN.
[...]
The firms Gebrüder Sulzer AG and VAT Buchs delivered components vital to South African uranium enrichment that supplied the fissionable material needed for the six atomic bombs produced by South Africa.
source

Thank god at least Cuba was there to lend help to the right side.