The six frontline states of Angola , Botswana , Mozambique , Tanzania , Zambia and Zimbabwe called on the South African government to release Nelson Mandela and all political prisoners. They urged the South African government to lift its ban on political parties such as the African National Congress (ANC) and the Pan Africanist Congress (PAC). They also urged the United States and other European countries to increase their pressure on South Africa and push it towards negotiation with South Africa's liberation movements. The following year on 16 September, The European Economic Community (EEC) imposed sanctions against South Africa in an effort to increase the pressure..
References

Weekly Mail Reporter. (1985). " The Week That Was", Weekly Mail : Vol 6 no 34|

M.Evans(1984/1985),' The front-line state,South africa and southen African Security military prospects and perspectives',from the department of history University of Zimbabwe,p.2