KEITH HARRIS, the bright and personable chairman of the investment bank Seymour Pierce, is many things to many people: financial entrepreneur, football fan, loyal adviser, outspoken pundit, devoted Manchester United shareholder. To quite a few recently, he has been the voice banging on about how Manchester United plc would be better off taken private. Drumming up some business, Keith? Or is there something else going on? “Ha, no, not at all,” he laughs, in his soft-spoken, hesitantly Tony Blair-ish way, “um, I’m in the business of giving advice, earning money and raising fees and I don’t think I would be doing anything that could earn a fee by creating a false market. For anyone to buy Man U it would require a substantial amount of money, that has to be a deterrent. Of course, um, if someone came along with that money and asked us to advise, then, well . . . ”

He smiles angelically. Harris, always good company, is often a hard man to pin down. Trained as an economist, he made his name as a banker at Morgan Grenfell, HSBC and Drexel Burnham, but has always mixed that glittering career with a lifelong love of football. That love seems to have diverted him off the path one or two times already, most notably when he agreed to chair the Football League, the body that administers clubs in Divisions One to Three.

He walked slap-bang into the row over ITV Digital television contracts — perhaps not so good a diversion. He was also the banker who arranged to sell a chunk of Man U to BSkyB (part-owned by News International, publisher of The Sunday Times) in 1999 — a deal that was blocked by the government.

But Harris tends to come up smiling. How does he do it? For a start, he has a broader range of friends than most: the guest list for his 50th birthday party earlier this year ranged from the bluntly entrepreneurial — Richard Desmond, whom he advised on buying Express Newspapers, Nigel Wray, who owns a chunk of Seymour Pierce — to the pukka pinstripe.

Only Harris could meld the two. Bred in Stockport, honed in Essex, now homed in Mayfair, he’s as happy chatting to his good mate Terry Venables as he is swapping canapes with City blue bloods. Even his friends note that the soft southern accent can harden into flatter vowels almost at the flick of a switch. Not many bankers can do that.

Social chameleon? “I don’t make an effort to do that,” he says, sounding pained at the description, “but I’ve always felt comfortable talking to people from all walks of life, frankly.” He is also a man with an eye for opportunity. No prizes for guessing who advised Chelsea Village, owner of Chelsea Football Club, on how to lay out the welcome mat for Roman Abramovich, its new Russian owner.

In fact, this year footie-mad Harris has clearly decided to shake things up. Now 50, he has separated from his second wife and bought out the investment bank he works for. The £7.4m Seymour Pierce buyout, backed partially by Alchemy, the venture-capital specialist, leaves Harris with a 20% stake and control of the agenda.

And the whisper in football is that Man U is now in his sights. And it’s not just business, it’s personal. Harris is a close friend of Martin Edwards, the former Man U club chairman who was forced to resign last season after lurid allegations about his private life. The man easing Edwards out was corporate heavyweight Sir Roy Gardner, boss of Centrica, the blue-chip giant, and chairman of Man U plc, a position Harris was, at one time, thought to covet.

You can work out the rest of the jigsaw yourself. (Don’t forget to add in Sir Alex Ferguson, his on-off relationship with various Irish Man U shareholders, and Mancunian resentment at outsiders’ influence — Gardner is Surrey-born. It doesn’t mean you end up with a clear picture of what’s going on, but it’s a lot of fun speculating.) So, is Harris out to get Gardner? Sitting in the plushly polished confines of his banking base in London’s W1, in his crisp blue shirt and co- ordinated tie, brown hair neatly coiffed, Harris — the very model of investment-banking probity — offers only injured innocence.

“A lot of people tell me I have ambitions at Man U, but, to be honest, I have less than 1% of the club’s shares. And right now I wish I had sold them when they were at £4.

“No, my point is that I think football’s flirtation with the public securities market has ended, and I think there are serious question marks over whether football clubs should be businesses that are public companies. There is a clear division between the interests of shareholders and other stakeholders, particularly the players and the fans.”

Would he take it private? “It would be quite expensive, you’d need more than £600m, but it’s the best-run company in the business of football, and has huge potential to earn more revenue and generate more income.”

Potential that isn’t being properly exploited? He won’t be drawn on that, but makes it clear that the recent loss of Man U chief executive Peter Kenyon to Chelsea is a major blow.