Theatrenow asked him about this role, as well as his pivotal part in Collateral Damage, a series of platform performances at the National Theatre, in response to the current international situation.

There have been a huge number of plays over the years about marital break-ups. In what way does Honour differ? "You're right, there have been, but it's an inexhaustible subject, in that all of us have been in a situation involving relationships, and we have either made — or will make — some of the mistakes that the characters in Honour do, or know people who have.

"The great appeal of Honour, to me, is that it's such a well-written play. There are four wonderful parts for actors, and the play has, deservedly, been a great success wherever it's been performed. The author is Australian, and the piece has been stage all over the Pacific, in Japan, Singapore, Australia, of course, and the States.

"One of the distinguishing things about Honour is that all four parts have an integrity and worth, without it being in any way a case of a false sense of balance or fairness between them."

As an actor, what's one of the great tests that a play has to pass? "I think a good benchmark of a really good play is whether you continue, as an actor, to find new things in the material, to be excited by it and therefore really look forward to getting on stage each evening: not in the sense of knowing that the audience will like the play but because you and the other members of the cast do." You're also appearing at the National in Collateral Damage? "Yes! I'm one of the instigators of this series of performances in reaction to the impending war with Iraq, which I think we should speak out against.

"Poll after poll have shown the majority opposed to the war, and we've had a huge, peaceful, protest march, letters to newspapers and so on, yet there's this sense that nothing can be done to stop the government dragging us into it. There's a phrase on placards — 'Not In My Name' — that sums it all up for me."

What do you hope the events at the National achieve? "Basically to stick our message up the government's nose — and any other orifices! It's essential that it be a powerful, provocative, political cabaret, of the sort that used to be such a feature of pre-Hitler Berlin.

"There will be readings from poetry and prose, but I hope there will be a lot of unscripted material and a sense of the evenings being real political cabaret.

"I'm a great fan of Rory Bremner and the two Johns, but you can achieve something far stronger, more scabrous, in the theatre than on television. It's wonderful that so many distinguished actors have agreed to take part. It's very brave of the National to stage it and let us get on with it, and hope we get a suitably high profile to embarrass our political masters."

Collateral Damage is at the Lyttleton Foyer in the National Theatre, at 5:15 PM. Each event lasts 45 minutes. Admission is free and unticketed, although numbers may be limited. Details of participants are subject to change.

March 7
Contributors include Eileen Atkins, Kevin Day, Lindsay Duncan, Jeremy Hardy, Hilton McRae, Corin Redgrave and members of the Anything Goes company

March 14
Contributors include Jeremy Hardy, Terry Jones, Joe Penhall, Vanessa Redgrave, Alan Rickman and John Sessions

March 21
Contributors include Judi Dench, Hanif Kureishi, Jude Law, Maggie Steed and Harriet Walter

March 28
Contributors include Patrick Marber, "Salam Ya Salan Cabaret" with Nadim Sawalha