BY the time I am up the narrow staircase Nick Wells is already apologising. “I bet you’ve not seen many offices as unglamorous as this?” he grins, waving his hand around.

Well, probably not. Wells’s base for TNT Mail UK, the Dutch-owned business-mail start-up that is taking on Royal Mail, is a small two-storey warehouse off a suburban road in outer Maidenhead.

The reception area downstairs fits two at a pinch. Wells’s cardboard-walled office, overlooked by the bedrooms of the semi-detached houses opposite, might fit four. Even the three named directors’ parking slots in the tiny car park outside seem more like desperate pragmatism than any folly of hubris.

And this will take on Royal Mail’s £6 billion business and 350-year-old monopoly? “We’ll probably move soon,” says Wells, rather sheepishly.

But appearances can be deceptive. Wells, 45, heavy-set with white hair clipped short and lugubrious face lightly tanned, is a self-made millionaire who created his fortune in direct mail before selling out to the Dutch postal group TPG (turnover €12 billion or £8.2 billion). Now he is using his old Maidenhead base, near Windsor, to plot the Dutch assault on the juicier bits of Royal Mail’s network.

As chief executive of TNT Mail, using a brand already known through TPG’s TNT Express and TNT Logistics divisions, Wells has launched a mail service for high-volume business customers, undercutting Royal Mail rates.

Since its low-key start last August, TNT Mail has signed up a range of businesses including the food firm Booker, mail- order company Express Gifts, telecoms group Caudwell Communications and Sky Television. Banks, credit-card companies and energy groups may soon follow.

TNT is not alone, of course. The German post office, using the DHL brand, is building a business-post network in Britain and a further five companies have so far been granted licences to compete with Royal Mail. This, after the years of haggling over the introduction of competition into British postal services, is how the invasion begins.

For Wells, backed by the logistics might of TNT, which has sophisticated distribution hubs across Britain handling its business-to-business parcel service, the full liberalisation of the mail market in January cannot come soon enough. By the end of this year, in a partially liberalised market, he expects to be carrying 600m items.

Under the initial access agreements negotiated with the postal regulator and Royal Mail — which allow licensed operators to compete for large-volume business mail — TNT picks up the mail and then feeds it into Royal Mail’s delivery system.

Eventually, he predicts, TNT Mail will establish its own delivery system to take business mail to consumers. He is not saying how yet, but he reiterates the obvious: “We are fortunate to have the TNT name and the support and resource of TNT’s owner, the TPG group, which is recognised in the Netherlands as providing the most efficient postal service in the world.”

But perhaps what’s most surprising is to find Wells, a high-profile character in UK direct mail and former chairman of the Institute of Sales Promotion, at the head of the Dutch assault.

For a start, when he sold his below-the-line firms to TPG in 2000 he obtained an earn-out deal that gave him a quarter share of a sale price of more than £20m. He has now finished that earn-out — he bought a holiday home in Switzerland named Chalet Margaux, after his favourite wine, with the proceeds — and he hardly seems the sort who would be keen to jump into anyone else’s corporate hierarchy.

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