De Klerk died after a battle against cancer at his home in the Fresnaye area of Cape Town, a spokesman for the F.W. de Klerk Foundation confirmed on Thursday.
De Klerk was a controversial figure in South Africa where many blamed him for violence against Black South Africans and anti-apartheid activists during his time in power, while some whites saw his efforts to end apartheid as a betrayal.
It was de Klerk who in a speech to South Africa's parliament on Feb. 2, 1990, announced that Mandela would be released from prison after 27 years. The announcement electrified a country that for decades had been scorned and sanctioned by much of the world for its brutal system of racial discrimination known as apartheid.
With South Africa's isolation deepening and its once-solid economy deteriorating, de Klerk, who had been elected president just five months earlier, also announced in the same speech the lifting of a ban on the African National Congress and other anti-apartheid political groups.
Amid gasps, several members of parliament members left the chamber as he spoke.
Nine days later, Mandela walked free.
Four years after that, Mandela was elected the country's first Black president as Black South Africans voted for the first time.
By then, de Klerk and Mandela had been awarded the Nobel Peace Prize in 1993 for their often-tense cooperation in moving South Africa away from institutionalized racism and toward democracy.