6 March 1982
F.W. de Klerk, then Minister of Minerals and Energy Affairs, was unanimously elected the new leader of the National Party (NP) in the Transvaal. His election came after Dr Andries Treurnicht quit the party. At the time the NP was the ruling party in South Africa as it came to power in 1948. It was F.W. de Klerk who, on 2 February, 1990 announced the release of Nelson Mandela as well as the unbanning of political parties. Subsequently, Mandela was released from prison on 11 February, 1990.
References

O’Malley, P. ‘1982’, from Nelson Mandela Centre of Memory, [online], available, at www.nelsonmandela.org.za (Accessed: 05 February 2013)|

South African History Online, ‘Frederik Willem de Klerk’, [online], available at www.sahisotry.org.za (Accessed: 05 February 2013)|

South African History Online, ‘Nelson Mandela is released from prison after 27 years’, [online], available at www.sahisotry.org.za (Accessed: 05 February 2013)