South Africa became a charter member of the United Nations (UN) on 7 November 1945. South Africa was one of the original 51 founding members of the UN from its inception on 24 October 1945. Political developments in South Africa particularly after the takeover of the government by the National Party (NP) in 1948 led to friction between the UN and South Africa. The implementation of the policy of apartheid by the NP put South Africa on the UN General Assembly's agenda. After the UN General Assembly tabled the issue of apartheid, South Africa's representation at the UN from 1955 to 1958 was greatly weakened. When South Africa repeatedly attempted to participate in the UN General Assembly's meetings, the country's delegation was prevented from taking its seat. Overtime the condemnation of apartheid grew, for example on 6 November 1962 the UN General Assembly passed a resolution condemning apartheid, the passing of resolution calling for a voluntary arms embargo. In 1971, the UN denounced the Bantustan (homeland system).  On 12 November 1974, the United Nations General Assembly suspended South Africa from participating in its work, due to international opposition to the policy of apartheid. This was followed by a resolution in 1977 on a mandatory arms embargo on South Africa. Resolutions calling for the expulsion of South Africa from the UN were repeatedly vetoed by Western powers who sat in the UN Security Council. Amongst those that refused to endorse the expulsion of South Africa were the United Kingdom, United States of America and France. South Africa was re-admitted to the UN General Assembly in 1994 following the dismantling of apartheid and its transition into democracy.
References

Anon, 'The United Nations and South Africa',from the United Nations [online], Available atwww.un.org.za[Accessed 26 October 2010]|

Anon, International cooperation - South Africa, from National Encyclopedia [online], Available at www.nationsencyclopedia.comAccessed 26 October 2010]|

Yehuda Zvi Blum, (1993),Eroding the United Nations Charter, Boston pp.48-51