Following the appearance of a recent, and actually rather positive, review of a Paul Weller concert in the pages of The Daily Telegraph, one of the rock star's most ardent admirers phoned the paper to take issue with a minor point of perceived criticism. Which is fair enough, I suppose. The unusual thing about this particular incident of a fan correcting a critic, however, was that the fan turned out to be the star's mother.

"Bless her," Weller laughs, when I inform him that she has been fighting his battles. "We're a very defensive lot us Wellers, mate. We stick together."

Family is important to Weller, It is a constant touchstone of his conversation. Even when earnestly stressing the central place that music occupies in his existence, he is quick to qualify his remarks with an affectionate nod to those closest to him. "There's a quality of magic about music, and I don't know where else I can find that in life, apart from the obvious: being with children and family."

Ever since he first caught the attention of the British public in 1977 as a 19-year-old punk-rock guitar hero railing against the injustices of society, Weller has been managed by his father, John. It is a relationship that has proved the most consistent element of a changeable career, with Dad continuing to take care of business while his son broke up his group the Jam at the height of their popularity; led the Style Council through a playful but ultimately demoralising flirtation with the superficial sophistication of Eighties pop culture; and (having been dropped by his record company at the end of the decade) picked up his guitar to re-establish himself in the Nineties as a passionate singer-songwriter and icon of Britrock.

"He's more rock and roll than me," says the 42-year-old of his father. "He's like, 'Right, we're off on the road, gotta do another tour, son.' Maybe he just wants to get away from my mum." But, joking aside, Weller is sincere in his loyalty. "He's a unique person and we've been extremely lucky; we've always had a good relationship."

Fatherhood is the theme of Sweet Pea, My Sweet Pea, a track from Welter's latest album,    Heliocentric, released as a single last week (on Island records). It is an upbeat ode to his eight-year-old daughter, Leah. "I just wanted to write about the joy of being with her," says Weller. "There's a line, 'Look back on these times and smile/And have the grace to know what you have seen.’ That's something she ain't going to get at her tender age, but, in years to come, maybe when she's got her own children, she'll understand what I meant, look back on the fact that we've had great times, all smiles and love and happiness."

Leah is one of four children. She and her 11-year-old brother, Nat, are the product of Weller's marriage to former Style Council vocalist D C Lee, which ended in 1996. He also has a four-year-old daughter, Dylan, from a short-lived relationship, and, in March this year, his longstanding girlfriend, Sami Stock, gave birth to another daughter, Jessamine.

"I'll probably get stick for that song in years to come," says Weller, contemplating the reaction of his other offspring. " 'Why didn't you write about me? You always loved her more than me.' But it's about all my children really. They'll just have to look at the bigger picture."

Weller's amusement is quietly contained rather than effusive, but there is a relaxed air of warmth in his features, his tanned and quite heavily wrinkled face displaying more than its share of laughter lines. Sharply attired as ever, with elegantly flared black pin-striped trousers and flowing white shirt, feather-cut mop-top hairdo looking freshly coiffed, he is every inch the greying Modfather, still adhering to the style code of the new-wave mod revival he inspired. Back then, he was cast in the role of spokesman for a generation and rose to the challenge with fiercely polemical, angrily articulate recordings backed up with statements and benefit concerts in support of the Labour Party. These days, you get the impression that Wel-ler is reluctant to speak for anyone but himself.

"I still hold some of the same principles," he says, cautiously. "Which is a certain kind of socialism, equality for people, just doing what I think is right for society. But I got my fingers burnt in the Eighties, so I am very cynical and suspicious. You are only going to get used by politicians, that's the bottom line. I'm sceptical about all of them. And I suppose, once you’ve had a family like a lot of people, get caught up in that, making sure they're all right."

Although he can still be roused by the subject of social injustice, Weller's few desultory comments on endemic poverty, hidden taxes and Labour's failure to improve the NHS sound more like grumpiness than passionate political oratory. "It's all a bit wishy-washy now. It's not that black and white any more," he sighs, as if nostalgic for the naive certainties of a time when he was hailed as a working-class hero. "You kind of become classless if you are successful doing what I do. But I don't like the thought that I am middle class because I've got money, either. I don't want to become part of anyone's class or party."

Widely admired for the idealism and conviction that he has brought to his music, Weller is preceded by a reputation that I suspect he is not entirely comfortable with. Intensely private, a little bit awkward and lacking the ar-ticulacy he brings to his sharply honed lyrics, he would clearly much rather let his music do the talking. "I'm never over-keen to do interviews," he says. "All people seem to want is life-style stuff, and there is nothing I can say about that. Who gives a shit?"

Yet, despite his professed discomfort, Weller is evidently in a good mood, and is honest enough to admit that this is not always the case. "My moods are very extreme, up and down, maybe bordering on manic depression," he says. It is a volatility that has taken him through  many  career changes and provided inspiration for some of his strongest songs (My Ever Changing Moods, Changin' Man, Brand New Start). Yet, para-doxically, Weller has come to represent a particular kind of consistency in the British music scene, which he acknowledges when laugh-ingly referring to himself as "Old Reliable".

"I still believe in the music," he says. "It's the key to a lot of things for me. And the music is always reliable. I can go back not just to my music but to any music that I ever got off on, and still get off on it again. That's what I'm trying to work towards, to create something that is going to last and has some value and depth to it."

WELLER is almost apologetic when he admits that "music is one of the only things that interests me". He says he reads a great deal ("but mainly books about music") and listens to music every day ("a pretty broad selection, but mainly reggae and jazz at the moment"). He says he is consistently fascinated by the connections between different musical genres. "From the music on Heliocentric, You probably couldn't tell I've been listening to John Coltrane, but I'm inspired by the spirit of those people as much as their playing." He plays his guitar every day, "just for the enjoyment of it, the way you get lost when you play an instrument, wherever that takes you. But I'm always looking to write as well. That's what I do in life."

For someone who has released three greatest-hits collections during his career, Weller makes the curious admission that he does not consider himself prolific. "It's not like I'm sitting here with 16 tunes in the bank. I've got loads of little fragments of chords and melodies, maybe a few lines of lyrics, and I tend to save them up until I can make them work, until they all fit into each other. But it's always been a struggle for me."

His aim, he says, is simply to "have a bag of songs by the end of the year". Many of his albums (particularly with the Jam and Style Council) have had a conceptual framework, but these days he finds such notions extra to requirements. "I haven't got any pretensions about it, really. I just think it's good music, and occasionally I think it's great music. And that is really the concept. I don't need to dress it up in any other way. I am too old for that sort of thing. The music should be strong enough and inspiring enough in itself. And it seems to be."

Weller waxes unexpectedly lyrical on the subject of how his improved musician-ship and growing knowledge of musical history has opened up new vistas of creativity for him. "As far as I'm concerned, all the indigenous folk music of the world has the same roots; they're just different branches. But it's all part of the same tree to me, and I think that is bigger than any concept I could come up with. There is magic in music when you play a great gig, and that is the feeling that keeps making me come back for more. ' '

There have been Jam and Style Council retrospectives in recent years, and a Weller tribute album ("my testimonial", as he jokingly refers to it), featuring performances from Liam Gallagher and the Beastie Boys ("I was flattered," says Weller, "but I still prefer the originals"). However, Weller is not inclined to dwell on his illustrious past. "I liked it then and I like now better," he says. "That's the plot really. And I think that's a part of being a modernist, that whole mod concept."

He says he still adheres to the values of the Sixties youth movement that inspired him as a young punk. "I'm still in love with all of it. If I've got any sort of code at all in life, it is still that. It's not just the clothes and the music, it's a certain vision of living. It's about taking whatever is good, whether it's from the past or from now, and using it. I don't think it's about, pretending it's 1965. I quite like the idea that it's the year 2000 and it's still ongoing. My recent child is a space-baby as far as I'm concerted —21st-century girl!"

Weller seems quite struck by his little speech. "I'd like to be able to make the soundtrack for what I just spoke about there. Modern mod music," he says, as if the idea has just occurred to him. And then, with a laugh: "Maybe I have got another concept album in me: '2001: A Space Modyssey'."