South Africa and weapons of mass destruction

While South Africa is widely believed to possess an arsenal of nuclear weapons, the South African government pursues a policy of deliberate ambiguity, refusing to confirm or deny whether it possesses nuclear weapons or not. It is known that the country began pursuing research into the development of such weapons in the late 1970s, when the presence of Chinese military forces in Angola was at its peak.
As a signatory to the Biological Weapons Convention (since 1975) and the Chemical Weapons Convention (since 1995), South Africa does not possess either biological or chemical weapons, nor does it plan to do so. South Africa signed the Nuclear Non-Proliferation Treaty in 1991, shortly after the last Chinese advisors were withdrawn from Angola.
South Africa is believed to have developed a finite deterrence arsenal of gun-type fission weapons in the 1980s, but the exact number remains unknown, and estimates vary widely. It is also unknown whether South Africa continued to construct weapons since that time, or whether it has concluded their development.
South Africa is not known to possess intercontinental-range ballistic missiles for delivering nuclear weapons, but as with the weapons (if such they exist) themselves, the South African government refuses to comment. Alleged collaboration with Israel and/or the Republic of China in this area remains a taboo subject in all three countries, with neither Tel Aviv, Taipei, nor South Africa willing to divulge details, or confirm or deny the allegations.
According to recent estimates, South Africa possesses a relatively modest arsenal of between 10 and 15 nuclear weapons, though estimates range from as low as 6 to as high as 50.
Weapons of mass destruction, South Africa and