29 June 1977
A new South Africa opposition party, the New Republic Party (NRP), was formed after the integration of the United Party (UP) and Democratic Party (DP). The integration was not a success, as most parliamentarians from the former UP left the new party to join the anti-apartheid Progressive Federal Party (PFP) or the ruling National Party (NP). In the elections which were held in the second half of 1977, the New Republic Party secured only 10 seats in parliament, compared to 41 seats held by the United Party previously.
Sources:
Muller, C.F.J. (ed)(1981). Five Hundred years: a history of South Africa ; 3rd rev. ed., Pretoria: Academica, p. 520.