For a man described as Africa's most famous living singer, and one whom Time magazine puts among the world's 100 most influential people, Youssou N'Dour cuts a disarmingly relaxed figure. Hiccuping after drinking some fizzy mineral water, he giggles.
"Forgive me," he says. "Pleased to meet you. These [hiccups] will go soon, I'm sure."
Here in London to promote his latest album, Rokku Mi Rokka ("Give and Take"), the Senegalese musician is in expansive mood. His Franglais burr is easy on the ear, and his smile lights up the room.
His latest album, released last autumn, is, in many ways, typical N'Dour fare: an infectious, highly rhythmic delight, his voice permeating everything like a snake in a hurry. As ever, he sings almost exclusively in Wolof, but for those of us not fluent in the language, its emotion shines through.
"For this album I was looking towards the music that touches me most," he explains. "African music, Cuban music, blues, maybe even some Latin sounds as well. You see, much of the music from the north of Senegal has its roots in all of these styles, and that's because when the slaves left Africa and went out into the world, they took with them their music. It has travelled far and wide since, and now it comes back to us with all sorts of different influences and colours. And it is this that I have tried to represent in my album, and why I have called it 'Give and Take'."
At least three of its minutes are geared towards capitalising on his global profile. "Wake Up (It's Africa Calling)" is the only song in English, and it reunites him with Neneh Cherry, with whom he scored an international hit 14 years ago in "7 Seconds". "Ever since that song, in 1994, I have been thinking about making an African response to it," he says. "That was me jumping to Neneh's style, to pop music. I wanted her to come over to my style now, and back to my roots."
Though it is perhaps the least convincing song on the record, its intentions are clear: the singer justifiably enjoys his international celebrity, and wants keenly to maintain it.
"For sure, for sure," he agrees. "Talent is never enough, and I work really hard to maintain my profile. For me, it is important, and for a great many reasons, oui?"
Born in Dakar in 1959, N'Dour began performing at the age of 12, much to his father's chagrin, who had wanted his son to pursue a more academic career – as a lawyer, perhaps, or a doctor, or a journalist, even, but certainly not a singer. "He was worried for me," N'Dour says. "You know, for reasons of drogue [drugs], bad living, things like this. But I was determined. We argued."
By the age of 20, N'Dour had turned professional, and quickly found success with his first band, Etoile de Dakar, right across Africa. "I never expected my music to travel," he says, "even when we became [locally] popular. But I remember travelling to Mali and hearing 2,000 people singing back my songs to me and crying. It was really just, ah, fantastique. I couldn't believe it, even though Mali is just next door to my country. To have an audience beyond home was not something I could even dream of."
Nevertheless, by 1987 his reputation had reached the ears of Peter Gabriel, with whom he collaborated on the latter's career defining So album. "Peter was wonderful to me, he played a really big part in my success," N'Dour says. Gabriel asked N'Dour to support him on a world tour, and "each night for 100 nights, Peter would introduce me, tell the crowd he was bringing out somebody very special."
The exposure landed N'Dour a major recording contract, and he went on to have success across the Western world as both a solo artist and as a collaborator, not just with Cherry, but also Bruce Springsteen, Wyclef Jean and Tracy Chapman. By the mid-1990s, he was Senegal's most famous man, and one of its richest, something he would be sure never to take for granted.
"With me, you see," he begins, "I feel like a missionnaire, almost. My music is not really my music, but something given to me by my country. So when I get success, I have to deliver something back."
To this end, he had set up a veritable empire in his homeland, and now employs more than 200 people to help him run a record label, a radio station, a nightclub and a newspaper. He has worked for Unicef, and also fronts his own humanitarian foundation that fights in Senegal's battle with malaria, as well as encouraging people from the provinces, particularly women, to come to the capital and enrol at the university.
All this is very philanthropic for a singer, Bonoesque. The majority of his Western counterparts would be far more likely to buy themselves a big house and spend days counting their money. N'Dour smiles broadly. "Well, I do have a big house, and I am very happy in it, but it has been my father's influence, I think, that has most encouraged me to do all of these things. When he finally accepted that I was to become singer, he told me to always carry myself with dignity and to do good for my country."
He does it well. Now 47, married and with seven children, he has done everything he ever set out to achieve, and more. In 1993, for example, he penned an African opera that premiered at the Opéra Bastille in Paris. He then wrote the anthem of the 1998 World Cup. In 2005, he was the only African artist to perform at Live 8, and two years ago appeared as the freed slave Olaudah Equiano in Michael Apted's Amazing Grace, a film about the abolitionist William Wilberforce.
"For much of my life I have worked really hard to have good career," he says. "I have had good life because of it, and I am a lucky man."
He is about to embark on a European tour, but increasingly he has wanted to take his foot off the pedal and enjoy the fruits of his many efforts a little more.
"I have a house on Cap-Vert. A small island off Africa; beautiful place. I like to go there and relax. It makes me feel, um..." He ruminates awhile here, a finger to his lips, before nodding his head, and smiling. "Ah, oui, it makes me feel peaceful."
'Rokku Mi Rokka' is out now on Nonesuch; Youssou N'Dour plays the IndigO2, London SE10 (0844 844 0002) on 1 April