WATCH: First known TV interview with Nelson Mandela

The Nelson Mandela Foundation, an NGO dedicated to Mandela’s memory, said that the 24-second footage was probably filmed in 1956 during the “Treason Trial,” which ended in 1961 with the acquittal of Mandela and dozens of others on charges of treason.

Mandela, who died in 2013 aged 95, became South Africa’s first black president in 1994. He won the Nobel Peace Prize in 1993 for his efforts to promote racial reconciliation in his racially scarred nation.

The footage shows a bearded and heavy-set Mandela wearing a grey suit and tie and standing before a plain paneled wall.

“From the very beginning, the African National Congress set itself the task of fighting against white supremacy,” Mandela said, referring to the movement that he went on to lead and which has been South Africa’s ruling party since the end of apartheid in 1994.

“We have always regarded as wrong for one racial group to dominate another racial group. And from the very beginning the African National Congress has fought, without hesitation, against all forms of racial discrimination and we shall continue to do so until freedom is achieved,” Mandela, who would have been around 38 at the time, said.

The Nelson Mandela Foundation said the interview took place at the Old Synagogue in Pretoria, where the Treason Trial was held and was broadcast on January 31, 1961 by a Netherlands television broadcaster, AVRO.

Previously, the first television interview with Mandela was thought to have been conducted in May, 1961, when he was in hiding. He would subsequently be arrested in 1962 and was only released from prison in 1990.