24 June 1986
Oliver Tambo the then President of the African National Congress (ANC) was responsible for holding together the various anti-apartheid movements and was sent overseas to mobilise resistance against apartheid. In Britain on the 24 June 1986, Tambo met with Lynda Chalker, Great Britain’s Foreign Office Minister, for the first time in a quest to end apartheid. Chalk emphasised on the need to suspend the use of violence as an important step to attaining a peaceful change in South Africa. African National Congress (ANC) officials; Thabo Mbeki and Aziz Pahad also attended the meeting. The meeting was said to be a success and useful as both the president and the minister were negotiating means to end apartheid without violence.
References

International Defense and Aid Fund for Southern Africa (1986), Southern Africa News Calendar: June and July 1986, from the International Defense and Aid Fund (I.A.D.F.) News, August, [online], Available at kora.matrix.msu.edu[Accessed: 20 June 2014]|African National Congress (ANC) Archives, Oliver Reginald Tambo, [online], Available at: ancarchives.org.za  [Accessed: 20 June 2014]|United Press International(1986), ‘London open talks with Tambo’, from the Los Angeles Times, 24 August, [online], Available at: articles.latimes.com  [Accessed: 20 June 2014]