Later this year, you'll be playing your first ever concert in Britain, at the Royal Albert Hall. Do you like the UK?

Yes, I used to live in London when I was seven for a couple of years because my family were dancers and they were dancing in London. I love London very much. I have a lot of friends there. All the artists I love, most of them are from England.

Such as?

I was very friendly with Tom Jones, the singer. You know Tom Jones?

Not personally…

Ah, OK. Also Paul McCartney. When we were kids we were listening to rock'n'roll and rock'n'roll comes from England. I believe the English and the Welsh, they invented it.

What do you think of British food?

It's OK. I prefer French food. You know what is my favourite dish? You have it in the pub. It's… how do you say it? Meat with mashed potatoes.

Bangers and mash?

That's it! I love bangers and mash.

These days, you divide your time between homes in Los Angeles and Switzerland. Do you still feel French?

Yes. When you're French, you're always French wherever you live. I live here [Los Angeles] because I can work here. Most of the musicians I play with are from LA. Also, people don't know me as much as in Europe so I can walk the streets easily without being recognised.

You're taking English lessons though…

I have a very nice lady who comes and we work every morning. I'm trying to be disciplined about it. All the "Tr" and "Th" sounds are difficult for French people but we're working on it.

Are you going to vote in the French elections?

Yes, of course, like everybody.

For Nicolas Sarkozy?

He's a friend of mine. I cannot say anything against him. I like the man very much but that has nothing to do with political respect. I've known Carla [Bruni-Sarkozy] for a long time – from before I met Sarkozy. I used to know her when she was a model.

She's recorded a few albums herself. Would you ever do a musical collaboration with her?

No.

Your debut single was released in 1960. How has the music industry changed since then?

Music, it has evolved but I don't really think of the past. It doesn't matter what it was before. For me, what is important is what we do today.

Do you like Lady Gaga?

Do I like what?

Lady Gaga…

Oh, yes [laughs]. Yes, she's great. She's crazy. I love her.

You're turning 70 in two years…

Unfortunately, yes, oh la la. But why not celebrate? We're still alive. We should always celebrate when we're still alive. Besides, getting older is a question of your mind. I don't feel old. It depends what you have in your head.

How old are you in your head?

I'm still 20! That's why I'm on tour again.

How do you find the energy?

I take care a lot. I do a lot of sport and training.

You ride Harley-Davidsons too, don't you?

Yes, of course. I have two Harley Davidsons over here. It's easier to ride in LA because the weather is so much better.

You were diagnosed with colon cancer in 2009…

It's finished, it's over. Just forget about that.

Um, OK. Is it true you once met quintessential Gallic boulevardier Maurice Chevalier?

Yes, I was 14 when I met him. He was a very gentle monsieur. He gave me a lot of advice. He asked me to sing him a few songs and he said to me: "Look, I don't know if you're going to be a great singer or not but you must always be careful with your entrance on stage and your exit. In the middle, you do what you can. You try to sing."

I always try to do that, to have an entrance that is very exciting, with a lot of special effects. When people go to see a show, they have to see something – not just to hear something.

You and your wife, Laeticia, adopted two Vietnamese baby girls in 2004 and 2008. You have two adult children from previous relationships – why did you decide to adopt?

It's a long story. My wife wanted to have some children and she could not have any. So she tried desperately for maybe 10 years and then couldn't get any. So we decided to adopt. We have two marvellous little girls from Vietnam and we're very happy with them.

It's great – they are so tender, they need so much love and we have much love to give. I don't see any difference between my real children and my adopted children.

You've been married four times…

Yes, but Laeticia and I have been married for 17 years, you know? It's a long time. Especially for a rock'n'roll star [laughs].

Do you have any advice for staying married?

No, I've no advice. The only thing is you have to be careful of love every day. Every day has to be a declaration of love.

You're known for your penchant for unfiltered Gitanes. Do you still smoke?

No, I don't smoke any more. It's a bad thing, a bad habit.

Has your voice changed as a result?

No, not at all. It didn't change anything, but I was not really inhaling the smoke. It was more of a nervous habit – I had to have a cigarette in my hand.