It’s been several years since Ali Campbell moved out of Birmingham, but the accent remains intact. In January, when the 49-year-old singer found himself back there, he was staying at the Hotel du Vin in the city centre. His brother Robin came to pick him up and the two became lost amid the regenerated city’s vastly altered landscape. “Nothing is the same as it was,” he says.

Like much of what he’ll go on to talk about, the words chime with an accidental sort of poignancy. Two months isn’t a long time – but then, two months ago, no one had any reason to suspect that, after so long together, the most successful reggae band in British history was on the brink of an acrimonious split. Right now though, UB40’s former front-man is no longer on speaking terms with Robin or the rest of the group. As Campbell himself says: “It takes a lot for eight members to stay together for 28 years. If you think about it, there’s only U2 – and there’s twice as many of us.”

There’s seemingly no going back. In February 30,000 Ugandan fans were gazing at them, many unaware that the band were honouring their final live commitment. By that time a storm of claims and counterclaims had already broken out. UB40 said that Campbell had placed the promotion of his solo album Running Free over his duties with the band. On January 29 a statement from Campbell’s solicitors stated that the singer had left to seek “a resolution to ongoing long-term issues that have arisen with the business managers of UB40”.

Come the very end, there were no awkward goodbyes. Since being treated for alcoholism, Campbell has kept a car waiting at the end of every UB40 show, lest he be lured into the recreational habits that come with the after-show party. In Kampala this meant that he could simply run off stage and, effectively, out of UB40. But that was February – and by this point the feud had already assumed a personal tone.

Taking exception to UB40’s contention that his “management” grievances were a smokescreen for his desire to put his solo career first, Campbell struck back, implying sour grapes. On Running Free’sarrival in the UK Top Ten last October, he said that Paul McCartney was quicker to offer his congratulations than any of UB40. “All I got was a text off Norman [Hassan, the trombonist] that said, ‘Well done Piggy.’” Campbell’s nickname, presumably? “Yes. Well, it used to be.”

The hurt comes out in brief bursts. During the course of a one-hour conversation, Campbell says things about his bandmates that I suspect he doesn’t really mean (a trait you hope he learns to curb before more excessive remarks end up being published).

His bullish demeanour is heightened by the news that the group’s keyboard player, Michael Virtue, has also announced his departure, citing similar grievances. Just as telling, though, is the sense of a man keen to reassure himself that he has made the right decision. He points across the corridor to a studio where Chrissie Hynde – who duetted with UB40 on their version of I Got You Babe – recently rehearsed.

“She saw my band and said how brilliant they sounded. Then she says: ‘I’ve almost had it with my band as well. We went into the studio and it just sounded like the Pretenders . . . and who wants to hear that apart from four fat lesbians in Ohio? I wanna do what you’re doing.’ ” Campbell may suggest he has inspired Hynde to find a new band, but the fact is that plenty of people remain fond of Campbell’s old one. Whatever you think of their Eighties mutation into a living reggae-lite jukebox, their first three albums – Signing Off, Present Arms and UB44 – deserve to be acknowledged alongside more fêted Midlands contemporaries such as the Specials and the Beat. As it happens, they rediscovered their militant edge in fine style on the unjustly overlooked Who You Fighting For in 2005.

When it comes to talking about the group’s infancy, Campbell needs no encouragement. “Back then, Birmingham was multiracial. We’ve gone backwards in that respect. If you go back to our old stomping ground – Balsall Heath and Sparkhill – black kids hang around with black kids and white kids stick with other whites.”

Campbell says that the values promoted by ensuing forms of music have changed the social scenery. “You would never have a band emerge now in the same way that UB40 did in 1979. But hip-hop came along and we inherited the segregation that it promotes.”

All the more reason, you would think, for them to stay together in 2008. By the same token, it’s nice to see him revelling in nostalgia for happier times. Like all bands starting out, he remembers UB40 as a band of simple pleasures. His friendship with Hynde dates back to 1980, when the Pretenders toured with UB40 and “shared their rider with us”. Two years later, substance abuse had killed off two members of the Pretenders, but UB40 had ingested nothing stronger than beer and weed. That all changed, remembers Campbell, with the release of UB44 in 1982.

Before recording it, they embarked on a tour of Europe. Bel-gium provided their introduction to cocaine. “You go there and the hotels have glass dressers with grooves for coke and little scoops for heroin – they date from the 1920s. So we were getting into the history of it. I remember going out and trying [cocaine], and just laughing at the top of our voices – you know, that big elation thing you feel the first time.

“Two years later we were in Bo-gotá with the crew marking out the stage with coke like it was chalk.”

Less enthusiastic was Campbell’s brother, Robin. Ali likens himself to their father, the Scottish folk singer Ian Campbell – “I did everything to excess,” says Ali, now a near-teetotal father of eight likening the comparatively timid Robin to their mother.

How to square the affectionate glint with which Campbell talks about UB40’s past with the open warfare being reluctantly conducted through publicists, solicitors and newsprint? Of course, UB40’s implosion may turn out to be temporary, but right now Kofi Anan, Terry Waite and a resurrected Mo Mowlam would struggle to establish common ground.

Campbell’s story centres on two bones of contention: (i) his alleged attempts to access details of the band’s finances; and (ii) his decision to make a solo album at the same time as UB40 were recording their 24th studio album, 24/7.

Leaving aside (i) for now, Campbell insists that his solo tracks were recorded in his spare time, without compromising the band’s schedule. For a while, relations between Campbell and the band must have been amicable – at least amicable enough for the singer and UB40 saxophonist Brian Travers to co-write nine songs for Running Free.

Campbell says that he tried to convince the band that publicity for his album would have a positive effect on the fortunes of 24/7. A further sticking point may have been his enlistment of guest vocalists such as Smokey Robinson, Mick Hucknall, Lemar and Katie Melua for his solo album. UB40’s album was also planned as a set of collaborations.

But if Campbell describes the clash of projects as surmountable, the same cannot be said of his problems with those running the band’s business affairs. “Every member knows I’ve got gripes with the management and had them for years. But their statement that I’ve left to pursue a solo career and [think] I’ve become bigger than the band is all about protecting management.”

Responding to Campbell’s words, UB40 – via their publicist – e-mailed to say that they were “disappointed that Ali Campbell continues to use and hide behind a variety of allegations against the other band members of UB40 and their supposed ‘management Svengalis’. Ali Campbell’s departure from UB40 has always been about promoting his solo career.”

Campbell alleges that the group are happy to live on their monthly allowance for the sake of a quiet life: “I want to find out where the rest of the money’s going.” As part of the statement sent to The Times the drummer James Brown suggests that Campbell – who once claimed to have bought his wife a £2,000 pair of Gucci jeans – may have become too used to living beyond his means. “The truth is UB40 were no longer prepared to fund the extravagant lifestyles of two band members. After being given an ultimatum by both Ali and Michael [Virtue] to sack our staff, some of whom have worked with us for nearly 30 years, we chose to ignore their ultimatum and they chose to leave.”

Campbell’s representatives dispute Brown’s words. They say Campbell requested four weeks off this June for a UK tour – and that prior to asking UB40 for this time, he checked with their agent to ensure there was no conflict with a planned UB40 tour of America. It seems, though, that the singer’s decision to play the solo shows in June this year compounded existing tensions.

Before last week fans were still holding out hope of a resolution. But on Saturday Brian Travers posted a notice on the group’s message board from which there may be no return. Angry at what he sees as the behaviour of “someone that could sell us out quite so easily”, he accused Campbell of “turning into an egomaniac” and using the dispute to “sell tickets for his upcoming tour”. On the afternoon of our meeting, Campbell had already read Travers’ sposting and pledged to “never share a stage with him again”.

Of course, if people have to move on, they will move on. Campbell asks if I want to see his new band and beckons me into the rehearsal room. Once in, it isn’t hard to see what so enthused Chrissie Hynde. Eight or nine skilled musicians busily run through the setlist for Campbell’s imminent Royal Albert Hall show. Scheduled to appear among these venerable reggae sessioneers are most of the guest singers on Running Free, Smokey Robinson included.

Fans will no doubt go home happy. But when Campbell opens his mouth to sing the lines, “All I can do, I’ve done/But memories won’t go”, will Red Red Wine have ever sounded sadder?

Bands...but not brothers: other rock and pop feuds

Bee Gees 1969 Robin Gibb leaves. Sudden stardom blamed. War of words in the press. Reconciliation leads to US chart-topper How Can You Mend a Broken Heart?

The Doors, 2005 Reform? Over Jim Morrison’s dead body. John Densmore prevented a version of the band featuring Robbie Krieger and Ray Manzarek calling themselves the Doors, prompting the joke: “When is a Door not a Door? When it’s subject to a lawsuit prohibiting it from calling itself a Door.”

The Beatles, 1970 A heartbroken Paul McCartney leaves the Fabs before going on to sue them for the dissolution of the Beatles’ contractual relationship.

Pink Floyd, 1987-present David Gilmour owns the name, but doesn’t want to make Pink Floyd albums. Roger Waters, who doesn’t, is more open to the idea. Don’t you hate it when that happens?

UB40: they came from Brum to save the world

1980 Band’s debut hit King/Food for Thought reaches No 4 in British charts.

1983 Red Red Wine hits No 1. Does the same in US five years later.

1987 UB40 become first reggae group to play Moscow.

1994 Ali Campbell and Pato Banton reach No 1 on a cover of the Equals’ 1968 hit Baby Come Back.

2005 UB40 play Cape Town leg of Live 8. Return to form with the album Who You Fighting For.

2008 Ali Campbell leaves UB40.

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