FW de Klerk, apartheid South Africa's last president, hailed Friday the successes seen in two decades of democracy, but scolded the ruling ANC for gross mismanagement and "increasingly aggressive" racial discrimination.
Speaking ahead of the 20th anniversary of South Africa's first free elections on Sunday, the Nobel peace laureate recalled the vote on April 27, 1994 as "our proudest moment as South Africans".
"To the astonishment of the whole world we had succeeded in overcoming centuries of bitterness, conflict, repression and division," he said.
He praised South Africa's return from the diplomatic wilderness and noted that in the last 20 years the economy had grown threefold, poverty had been reduced and "a vigorous and self-confident black middle class" had emerged.
"Many aspects of our society have transformed out of all recognition," he said.
But De Klerk, who lifted a ban on the African National Congress and in 1990 released Nelson Mandela from prison, also chastised the ruling party for squandering its democratic inheritance.
Under ANC rule, he said, public institutions "have been commandeered to promote partisan political objectives".
"People are appointed to key posts -- not because of their qualifications, experience and impartiality as required by the constitution - but because of their political connections."
"This has gone hand in hand with increasingly rampant corruption -- some of it sanctioned at the highest levels of the state."
De Klerk, who shared the Nobel peace prize with Mandela in 1993, said it was now an "unacceptable fact" that South Africa is a more unequal society than it was in 1994.
Once feted for negotiating a democratic transition with Mandela, De Klerk has at times sullied his reputation by appearing to justify apartheid.
His outspoken views on the role of whites in the country -- who in general remain much better off than black South Africans -- has also raised ire.
De Klerk also spoke out Friday against what he called "increasingly aggressive -- and apparently permanent -- race-based discrimination".
He said policies like those designed to put businesses in black hands had "led to a situation where the prospects of citizens are increasingly determined by the colour of their skin and not the content of their character".
"We are approaching the point where we will no longer be able to claim that we are a non-racial democracy."
The 20th anniversary of democracy coincides with South Africa's fifth democratic election on May 7.
The ANC is expected to win handsomely, returning embattled President Jacob Zuma for a second term.
The party has promised a "second phase of the transition" with more radical policies to rebalance wealth.