In an age of guilty pleasures and 1980s nostalgia no pop star is exempt from rehabilitation, not even Rick Astley. There is, however, an exception to the rule. He sits in the conservatory of his Surrey mansion and sips a cappuccino as he contemplates the hostility he provokes.

“I fully understand why I’ve alienated many people,” Mick Hucknall admits in his soft-spoken Manchester accent, “but while I have certain regrets, I can’t honestly say that I think I’d be able to do it another way. I can’t imagine that I’d just be able to lay down, shut up and stay in my little box and be the smooth soul guy and just talk about the ladies.”

Like his friend Tony Blair, Hucknall is an odd mix of charm and divisiveness. His group Simply Red is one of Britain’s most successful acts, selling almost 50m albums since their debut in 1985. He has a honeyed voice that beguiles and seduces. Hits such as “Holding Back the Years” and “If You Don’t Know Me By Now” have brought him international stardom. Yet outside his fan base there is no shortage of Hucknall-haters who would willingly throttle him.

The singer’s immodesty is one reason. I find him to be open and jovial, but he does have a tendency to begin anecdotes with the words: “I had a conversation once with Tony Blair ... ”

Critics deride the long-term Labour party supporter as a champagne socialist. His playboy reputation, squiring women who appear to have been picked at random from a celebrity telephone directory – the list reputedly includes Brigitte Nielsen, Steffi Graf, Catherine Zeta-Jones, Helena Christiansen – is greeted with unkind incredulity. His physical appearance, especially his luxuriant red hair, has attracted a stream of vitriol: “Ginger Lothario”, “Ginger Whinger” and so on.

“The hair is another issue,” he sighs. “Red rag to a bull. What do they say in showbiz? If you’ve got it, flaunt it.”

These days the 47-year-old no longer flaunts it like he used to. The corkscrew hair is cropped and fading in colour. A greying goatee beard frames his face, which has lost the boozy puffiness of past years. He wears a beige jumper, blue shirt and brown trousers. A ruby tooth glints in his mouth when he smiles, the only evidence of ostentation.

Hucknall has settled down. His days as a “drunken womaniser”, as he puts it, are over. He has a long-term partner and a baby girl. A musical corner has been turned, too. Next month he releases his first album under his own name, a collection of covers of songs by one of his favourite vocalists, the 1950s singer Bobby Bland, “an unsung hero” in Hucknall’s words, which takes him back to the unpolished blues and R&B he grew up listening to as a working-class boy in Manchester. It is a far cry from his sleek work with Simply Red, whose back catalogue he claims he will no longer perform from 2010.

“Simply Red are not splitting up,” he insists. “How can I split with myself? I’m the principal songwriter, I’m the bandleader, I’m the lead singer. It’s really about closing down the catalogue. If I go under my own name, I can start a whole new body of work, plus if I feel like it I might do just one or two Simply Red songs.”

The cynic in me detects a door being left ajar for the inevitable Simply Red comeback. “The great Sinatra did that, so I think you can get away with it,” Hucknall chuckles, citing the brazenly titled track “Let Me Try Again” from Sinatra’s post-“retirement” album Ol’ Blue Eyes Is Back.

“So maybe I’ll cover that if I do a Simply Red comeback.” The ruby tooth flashes as he gives a rascally grin.

His musical roots lie, oddly enough, in punk rock. Hard though it is to picture the crooner of “If You Don’t Know Me By Now” pogo-ing to the Sex Pistols in 1976, Hucknall, hair shaved into a jaunty tuft, was among Manchester’s first wave of punks. His band Frantic Elevators shared rehearsal space with Warsaw, soon to be renamed Joy Division. “They were all dressed in black. We always thought they were dead miserable.”

His love of soul and R&B reasserted itself as Frantic Elevators morphed into Simply Red in the 1980s. Their first album was meant to have a gritty, 1960s-retro feel, but the producer gave the songs a contemporary sound, initially to Hucknall’s chagrin though he grew attracted to the style as the band’s popularity grew.

He is, however, candid enough to admit their songs became too glossy. “Radio stations loved ‘If You Don’t Know Me By Now’ and ‘It’s Only Love’, and then all of a sudden you think, ‘I need to do more of those because they like that’. Before you know it, you’re starting to make stuff that becomes what you think they want, not what you actually want to create yourself.”

This is a startling admission from a man who declared two years ago that he was “one of the best singer-songwriters this country has produced”, and who will be discussing his songwriting on a Sky Arts “Songbook” programme later this month. When asked if he stands by the quote, he looks remorseful. “Did I say that? Well, I regret it. The only reason I would have said it is that I’ve been so misinterpreted over the years that I became exasperated by the whole damn thing.”

Hucknall ascribes his falling out with the media to politics. “There I was in 1985, in the midst of euphoric Thatcherism, telling the media that I hated Margaret Thatcher, I hate her philosophy, I hate her policies, she has destroyed the north of England. I was immediately alienated by taking that stance. I feel that somehow I’ve been the antithesis of contemporary culture since I started in the mid-1980s.”

It is the sort of grandiose remark that his detractors leap on. The singer is unabashed. “One of the things that I’ve perversely enjoyed is not fitting into brackets, because to my punk-generation mind the whole point is to f*** with it, don’t be what it says on the tin, fight that.” He raises a defiant middle finger. I don’t quite believe him – the rough press he has received clearly rankles – but I suspect the time is ripe for a reassessment.

The rise of a younger generation of white soul singers led by Amy Winehouse has brought the voice back into fashion, and even his fiercest critics would agree that Hucknall’s creamy singing is very appealing. So what state is his voice in today?

“It’s in the best state it’s ever been, which is unusual for people when they get to be my age in this business because it’s usually fried.” Why? “Er, because I’ve not over-indulged in cocaine. I think cocaine is the killer. Smoking is bad, but the biggest underestimation of coke is the damage it does to your nose, which is vital to singing. My poisons were mainly vast amounts of champagne, a bit of weed and chasing women. That was me in a nutshell.”

A few years ago he took a DNA test. “It turns out I’m Irish, Basque and Ashkenazi,” he laughs. “When I told my dad, he said [Hucknall adopts a gruff northern accent] ‘That’ll be the Spanish sea captain, then. There was always talk of a Spanish sea captain in the family.’ So what with me being contradictory, perverse, wanting to go left when everybody else goes right, and you think, Paddy-Basque ... It all starts to make sense.”

Mick Hucknall’s first solo album, ‘Tribute to Bobby’, is released on May 19. He appears in ‘Songbook’ on Sky Arts on May 22