John Kani talks to Terry Grimley about his new play.

A year ago this month John Kani was playing Claudius at Stratford in Janet Suzman's production of Hamlet from Cape Town, one of the first international contributions to the RSC's Complete Works festival.

Opinions about the production were mixed, but I thought it was fresh and exhilarating. Yet it was delivered under the shadow of tragedy, as the actor originally cast as Guildenstern, Brett Goldin, was murdered in a car-jacking days before the company was due to fly to Britain.

Looking back, Kani recalls a difficult time for him and his colleagues.

"We were having open rehearsals in Cape Town which were sold out – this is how South Africa has taken to Shakespeare. And then on the Friday night we heard this young man had disappeared and was killed. The case is still current in South Africa.

"The cast only had three seniors – Dorothy who played Gertrude, the gentleman who played Polonius, and myself. The rest were young people, so we had a situation where we even called in a psychologist to talk to them. They were all students at the University of Cape Town within a few years of each other.

"Brett was almost like a jester of the group – he made everybody laugh. He had so many dreams – it frightens you when you think they were cut short.

"It was an incredible experience. As you know, Hamlet is constantly talking about death and killing and people dying, and the cast was going through two levels of emotions. It wasn't an easy time but I must commend the cast and Janet's unwavering discipline."

Kani, who was invited back to Stratford for the closing celebrations for the Complete Works last month and was touched to be stopped in the street by people who told him how much they enjoyed Hamlet, recalls his earliest encounter with Shakespeare.

"My teacher made us read it in Xhosa. When later I read the English version I thought Shakespeare wasn't as good as the original Xhosa."

In a famous earlier collaboration with Janet Suzman as director he was the first black actor to play Othello in South Africa. This was 1987 and not everyone was ready for it, with white members of the audience walking out when he kissed Desdemona. A policeman wanted to know why he was doing this when it was not indicated in the text.

Kani was excited to think the policeman had actually read the play, "but I said to him, you know, when Laurence Olivier and Maggie Smith did it he could not kiss her because he would leave a black smudge on her face. I don't have that problem."

Now Kani is returning to the West Midlands in his post-apartheid drama Nothing But the Truth , which comes to Birmingham Rep next week. The first play he wrote entirely on his own – he is best known for his collaborations with the playwright Athol Fugard and fellow actor Winston Ntshona – it was first staged in South Africa in 2003, and has since been performed in New York, Los Angeles and Sydney.

And by a happy coincidence Peter Brook's revival of Kani's most celebrated collaboration with Fugard and Ntshona, Sizwe Banzi is Dead, comes to Warwick Arts Centre from May 29 to June 2. Frustratingly for Kani, there is no overlap which would enable him to travel over to Coventry to see it.

Last summer he and Ntshona revived Sizwe Banzi as part of the 50th anniversary commemoration of a women's protest march against South Africa's notorious pass laws.

"It was sold out in every venue and I was finding that young black audiences were interested in a play that deals with a crisis of identity. It's not so much about racism."

Kani and Ntshona then brought the play to the National Theatre in London, where it played for three weeks and Peter Brook came to visit them.

It was a surprise to find that a play devised in a very specific context was now being seen as a classic about the human condition. In a world made more authoritarian by the war on terror, the dilemma of the individual who is a non-person without his documents becomes ever easier to identify with.

"At the National Theatre everyone agreed about the resonance," says Kani. "In a world of terror suspects where even the UK is bringing in identity cards – which we see as a pass card – that's exactly how the pass laws started.

"Many people were talking about that. So it's strange to go back to Sizwe Banzi after 35 years, as an elderly gentleman in my 60s now, and find that it is regarded as a great classic. At the time it was really just a story of this man trying to make it through the day and tangled by the nightmare of the pass laws."

Nothing But the Truth is about South Africa more than a decade on from the end of the apartheid era, yet it is rooted in that time. It began as a tribute to Kani's younger brother, a poet who was shot dead by police when he was reciting at a funeral.

"In 1995/6 I supported the truth and reconciliation process wholeheartedly for the nation, but when it came to me I did not apply the process to myself. I could not answer the question did I forgive the white policeman who shot my brother?

"The same answer is difficult now. As years go by, every time I think about him I'm very angry at the loss of a young life, but I thought perhaps it was time for me to bring closure.

"It was supposed to be the story of a young poet trying to go on writing good poetry but the story took a turn away from him to these two brothers, one living quietly in South Africa and the other a firebrand who left the country, ended up in London and died there in 2000.

"It's a story of sibling rivalry, secrets and family, truth and reconciliation."

It's well known that in post-apartheid South Africa there was a certain tension between those who participated in the struggle at home and others who returned from exile, though Kani thinks it can be over-stated.

"It was not such an issue. But people who left South Africa came to Europe and got themselves jobs and skills. It appeared that whenever a job opportunity came up they were the ones getting it, whereas those who stayed in South Africa were handicapped by an education system designed for blacks."

But despite such passing frictions, Kani is proud of the progress South Africa has made and optimistic about its future.

"In 14 years we are better off than many countries in the West. We have done incredibly well. I was so pleased when I watched TV and saw the Reverend Ian Paisley and Martin McGuinness, and I said 'that's truth and reconciliation'.

"I know South Africa was involved in some way in discussing the process, so we're very proud of what's happening in Northern Ireland.

"Of course we're faced with other challenges – crime, the AIDS pandemic. We are not going to solve our problems in 14 years. The police were never set up to investigate crime, but now we are slowly getting on top of crime, AIDS, nature conservation. I just believe South Africa is a very strong place."

Theatre, he acknowledges, found itself in limbo for a while after the collapse of the old enemy. That is, the kind of political theatre with which he was associated at Johannesburg's celebrated Market Theatre – there was always a successful commercial theatre which still thrives today.

"But South African theatre is beginning to find its voice again. Younger people are writing plays examining today's society. We are laughing more, black stand-up is looking at how ridiculous the past was and how we are doing with the rainbow nation where everything is democratic."

Looking back to the heroic days of the Market Theatre in the 1970s, he points out that it was the media which dubbed the work he and his colleagues did "political" theatre. Their focus was simply on telling stories.

"That's what theatre is – that wonderful once upon-a-time dream when you sit down and you're told a story. And at the end you stand up and feel a little bit more confident."

* Nothing But The Truth is at Birmingham Repertory Theatre from Wednesday to Saturday next week (Box office: 0121 236 4455). Sizwe Banzi Is Dead, directed by Peter Brook, is performed (in French with English surtitles) by the Theatre des Bouffes du Nord at Warwick Arts Centre, Coventry, from May 29 to June 2 (Box office: 024 7652 4524).