It's odd the things that go through your mind when you are on the way to interview somebody. I had arranged to meet F.W. de Klerk at the Shelbourne Hotel and, on the way in, an old memory returned of a day in 1970 when the Springboks came to play in Dublin. I was one of many protesters at Lansdowne Road and, later, outside the Shelbourne where the teams had gathered for an after-match reception. At one point the late Hilary Boyle and I managed to gain entrance to the lobby to register our protest on a one-to-one basis but, finding ourselves largely ignored, we made our excuses and left.

At that time, the Afrikaner monolith seemed as impregnable and fissure-proof as the Stalinist monolith in Eastern Europe or the Shah's rule in Iran. Had someone told me that three decades on, I would be sharing a plate of ham sandwiches in the Grace Kelly suite with the last white head of state in Africa, a man who had precipitated and presided over the dismantling of the unjust apartheid regime, I would not have believed it any more than a prediction that the Berlin Wall would one day end up in souvenir shops.

De Klerk was here to promote his newly-published autobiography, The Last Trek - A New Beginning*. The book is an Apologia pro Vita Sua, frequently defensive in tone as it deals with the various controversies surrounding its author's time in office. But in person De Klerk - who will be 63 in March - is affable and relaxed and responds in a matter-of-fact way no matter what the question. The only possible sign of any underlying tension is the fact that he chainsmokes Peter Stuyvesant throughout the interview.

He is accompanied by his striking Greek wife, Elita, and long-time personal assistant, Dave Steward. The latter helped with writing the book, coining some of its more felicitous phrases (De Klerk's first language is Afrikaans), and he also interjects from time to time during our conversation.

De Klerk is a frequent visitor to Ireland and says Afrikaners have a "soft place" for the Irish, stemming from the "very good" help they received from the exiles who set up an Irish Brigade in South Africa during the Boer War.

He is wary of direct comparisons between the Irish peace process and the democratic transformation of South Africa. But he concedes there are "some universal lessons" that can be applied to such situations.

With the Irish process hamstrung by the issue of decommissioning paramilitary weapons, are there any useful parallels with South Africa? He recalls that decommissioning never took place as fully or comprehensively in his country as it was supposed to under the terms agreed, but that the issue was not permitted to derail the process.

"We had to face up to the fact that while we continued to work at it we could not allow the lack of diligent compliance to really stop the wagon." He continues: "Somehow or another, however difficult the intermediate deadlock or crisis might be, you've got to go beyond it, you've got to move forward, you've got to take the bull by the horns and keep pushing forward."

He grins when told that Irish nationalists and others often wonder when a "unionist De Klerk" is going to emerge to make peace with the traditional enemy, but shies away from drawing an analogy between the unionists and Afrikanerdom. "I see a comparison in the process which is taking place and that is that people on both sides, who have held firm attitudes which were at the bottom of the conflict in the past, are now changing their attitudes."

A sense of disappointment comes across in the book at the fact that plans and schemes envisaged for a durable form of power-sharing involving his party and the African National Congress eventually came to naught. So was he suggesting that South Africa was in danger of becoming, in effect, a one-party state (as it was, in essence, under Afrikaner rule)? "Not a danger, but I see a shadow of that possibility."

Excerpts from his book in the press featuring bitter criticisms of Nelson Mandela have attracted considerable publicity. When Mandela succeeded him as president and De Klerk became one of two deputy presidents, a protracted saga ensued involving official residences. As De Klerk portrays it, he was moved from pillar to post, or from mansion to mansion. It was finally decided he would stay in a house called Overvaal but when De Klerk said the place needed extensive refurbishing, Mandela insisted on a personal inspection to verify this was indeed the case - De Klerk calls it "the final humiliation".

Recalling a "tirade" against him by Mandela on another occasion, De Klerk writes: "As he piled insult upon insult, I found it difficult to control my fury." But he adds: "National interest demanded that I should transcend my own ego."

When the pair were jointly awarded the Nobel Peace Prize, Mandela attacked him in interviews even before they got to Oslo. "Apparently he was not pleased by the decision to include me in the award."

De Klerk says the criticisms have been taken out of context. "Seen just like that in an extract, they seem a little harsh. On the other hand I say also many good things about him in the book, which didn't appear in the extracts. Maybe the most fundamental point is that I make it absolutely clear that when it really came to the push on important issues, both of us managed always to rise above those tensions."

Acknowledging that Mandela comes across in the book as being vindictive on occasion, De Klerk says it is all based on fact. "Anybody thinking that I had an axe to grind and that I used the book to get at him would really be making a mistake." After the book was completed the two men met for a chat over a cup of coffee. "We had a very good discussion and our parting words were, `We must now early in 1999 find a date and have lunch together'."

De Klerk himself has, of course, not escaped criticism, especially in relation to illegal acts of violence against the ANC carried out by elements in the security forces when he was in government. "The fact is, I didn't know. I didn't know because it was hidden from me, as it was hidden from other political decision-makers. And some of the heads of police and the defence forces, it was also hidden from them." He is reluctant to discuss the specifics of a dispute between himself and South Africa's Truth and Reconciliation Commission because the matter is still sub judice.

Now retired from party politics, De Klerk seems set to become a Jimmy Carter-like figure, sitting on platforms and attending conferences for various good causes around the world. Enoch Powell said all political careers end in failure: De Klerk is unusual in that he deliberately engineered his own demise as South Africa's president. Unlike others nearer home, instead of resisting change, he saw it coming, embraced it and sought to manage the way it developed. History may say his biggest success was the way he did himself out of a job. But while the book shows he still has a few scores to settle, he has no regrets about the consequences of his actions. Enjoying the unseasonal sunshine streaming in from St Stephen's Green, Frederik Willem de Klerk drags on his cigarette and says: "I am not complaining.'

* Macmillan Publishers, London. £20 sterling hardback.