The new South Africa: F W de Klerk's long trek

They were there to celebrate the 70th birthday of FW de Klerk, the last white president of South Africa, and the man who formally ended 342 years of white rule 12 years ago. Thabo Mbeki, who took over from Mandela as President in 1999, was not there, but his wife, Zanelle, was, as was the widely respected Finance Minister, Trevor Manuel (another possible next president). All greeted De Klerk, not as the leader of one of the most repressive and hated governments of its day, but as a friend and respected ambassador for the new South Africa.

The ruling ANC party has long taken its cue from Mandela, and in South Africa past grievances, horrific as they were, were put firmly in the past a dozen years ago. Forgiveness comes astonishingly easily in this extraordinary country.

Mandela, visibly ageing (he will be 88 in July) but with mind and eye as bright as ever, was in his best form. He has a way on these occasions of gently playing with his audience, drawing it in with a mock self-deprecating and impish style, before delivering the serious message he wants to get across. Last night was classic Mandela.

He knew he was a surprise guest (and De Klerk pretended to go along with the surprise) so he began with a surprise, delivering his opening paragraph in fluent Afrikaans, the language of apartheid so hated by the ANC in the old days of the struggle. It was seen by the audience for what it was: an enormous honour to his old enemy.

"Dis goed om te sien hoe ons saam oud word," he began ("It's good to see us growing old together"). Then, with one of his impish glances at the bald De Klerk, he went on (still in Afrikaans): "Of course I still have my hair, even though it's much greyer. But it wasn't you who made me go grey - and I sincerely hope it wasn't me who made your hair fall out." The room collapsed into hilarious laughter and Mandela had them where he wanted them.

Switching into English, Mandela said he was happy that the two of them, as "retired and almost forgotten men" (more laughter) were gently ageing together. The much younger De Klerk looked startled, and again Mandela beautifully milked the moment. "You may gloat that you are 20 years behind me in this process. But remember I spent 30 years idly relaxing on islands and in other resorts while you were battling it out with the maddening crowd. So in reality we are of equal age." It brought the house down.

The speech, short though it was, in many ways summed up the relationship and differences between the two men over all of their lives: De Klerk, born into the most traditional of Afrikaner-Boer backgrounds, and Mandela, the Xhosa chief who spend a lifetime fighting him and his white-supremacist class, come from the opposite poles of 20th-century South Africa.

Mandela had some serious points he had come to Cape Town to make. He wanted, he said, to give De Klerk his due credit for the shared moments in history which "in all humility on our parts, might have helped to shape our country, our continent, and, in modest ways, the world". And he referred to the "remarkable" fact that "this direct descendant of Prime Minister Hans Strijdom [uncle] and Senator Jan de Klerk [father], both stalwarts of the National Party and therefore of apartheid, could stand up when the moment came to decisively start the total dismantling of apartheid and minority rule".

It was an extraordinary and generous speech, even from one of the most generous-spirited men in the world today, acknowledging (and he did not always acknowledge it), the role De Klerk played in bringing South Africa to where it is today. It has been a long road for both of them.

For De Klerk, it has been more of a trek (the Afrikaans word) than a road, and probably not even one he deliberately set out on. Seventy years ago, on 18 March 1936, the South Africa he was born into was a very different one, and not even the more far-sighted, such as Jan Smuts (a political enemy of the De Klerks), could have glimpsed today's black-governed, prosperous and united nation.

"I was born into a family that had been closely involved in the whole historic development of the Afrikaner nation and its struggle for freedom," says De Klerk. His "struggle for freedom" was against the British, who hanged a De Klerk for treason when they first occupied the Cape during the Napoleonic Wars, and imprisoned his grandfather in the Boer War. But the history of the De Klerks in South Africa goes all the way back to the earliest days of white rule, when a De Klerk arrived from Holland in 1688.

They were Huguenots, persecuted by Cardinal Richelieu, and refugees across Europe. Those who made it to the magical Cape could scarcely believe their good fortune as they watched the vines they had brought grow in the fertile soil around Stellenbosch, where land was abundant and cheap (and not far from where De Klerk still grows grapes). There were voortrekker De Klerks who took their entire families on ox-drawn wagons deep into the veldt to get as far as possible from the hated British. There were De Klerks who fought against the Zulus and whose deeds he was brought up on, and there was grandfather Willem de Klerk, a minister of the Reformed Church, who was one of the founders of the National Party in 1914.

FW is proud of them all, and unflinchingly proud of his Afrikaner heritage. He is not so proud of apartheid, but argues that the Afrikaners, decent, God-fearing people at heart, were forced to go down that route by the circumstances of their own turbulent history.

"We need to acknowledge the deep injustices of apartheid," he wrote in his autobiography. "But we must also acknowledge the historical dilemma in which Afrikaners, as a separate nation with their own right to independence, found themselves."

If you want repentance, you will not get it from FW - and there are many who will argue that De Klerk only ended apartheid because he was forced into it.

After the 1994 election he worked for the new South Africa as vigorously as he worked for the old, initially taking up the role of Executive Deputy President in Mandela's government of national unity which embraced all the parties, including Mangosutu Buthelezi's Inkatha Freedom Party. "I was very enthusiastic about the concept of the government of national unity," he says now. "It rendered a very important service to South Africa and all its people."

Certainly it helped to pave the way to a transition far smoother than the world could ever have expected. But it was a honeymoon period, with ANC ministers growing increasingly resentful of what they saw as an attempt by the National Party to keep their rights and privileges of power under a different guise. De Klerk and his strong-willed wife, Merike, lived on in the presidential house, and for a while their lives barely altered. But behind the scenes all was not well: there were fights in cabinet, which to De Klerk's horror the ANC insisted should be made public, and above all, Mandela and De Klerk did not get on. Nor did he bond with Mbeki, to whom Mandela was increasingly prepared to pass the reins of real power.

I interviewed De Klerk during this period, following up an interview I had done in the very grand state president's office a week before the election. He claimed to be getting on well with both Mandela and Mbeki, his fellow deputy president, but he was still talking of the resurgence of a new national party which would have much wider appeal than an ANC which he believed would inevitably splinter. "I believe my party is poised as the party with the greatest growth potential," he said. "We will be looking for a win in the next election." I looked for a flash of irony, but there was none - he meant it.

It was never to be, of course. After 18 months he took his party out of government and into opposition, a move which was widely seen as suicidal for the party - which indeed it was. The party disintegrated within months, its remnants subsumed into the broad ANC church.

"The party did not disappear because we left government," he says now. "But after I left, it failed to attract public support."

His retirement from the party, he says, was motivated by a desire to rejuvenate it and to distance it from the days of apartheid. But that never worked either.

By that stage he had moved on again, assuming more and more the role of international statesman. He became a sought-after speaker (and he is a brilliant one) at conferences and meetings all over the world. He had also moved on from Merike (who was later brutally murdered), falling in love with his present wife, Elita, then the wife of a Greek shipping millionaire.

His new interest today is the Global Leadership Foundation, which he founded two years ago, and whose aim is to help leaders of countries deal with the myriad problems they face in the modern world. He has brought together a group of people who have been world leaders - Michel Rocard of France, Mike Moore, former New Zealand premier, IK Gujral, former prime minister of India, Douglas Hurd and former premiers of Botswana, Portugal, Colombia, Mauritius and half a dozen others. Mandela is one of his patrons, as is his old friend George Bush Snr.

The trigger for it was 9/11, which made the world aware that events in the most remote of countries could have a huge impact on even the most powerful nation in the world. De Klerk had become very aware that new countries and new governments had little idea of where to turn for help, and how best to get it. On a confidential basis his team now advises two countries at prime-minister level, with another four close to signing. They don't get charged - De Klerk raises the money from international donors. He passionately believes he and his fellow former leaders can make a difference where it matters.

That and his speaking tours take him around the world. But this weekend he will be back on his farm near Paarl, 30 miles outside Cape Town, where his ancestors first farmed more than 300 years ago. He has come full circle.