Mark Price is ready to make two new year predictions. The managing director of Waitrose, the supermarket chain, says: “The first is that all our larger rivals will announce massive price cuts in January.

“The second is that their gross margins will still be higher at the end of year than at the beginning.” The self-styled “chubby grocer” may not be getting leaner, but he’s certainly becoming that bit meaner.

Ironically, given his surname, price is his present bugbear. He is fed up with Waitrose being perceived as being far more expensive than the likes of Tesco and Asda, which, he argues, regularly announce multi-million-pound price cuts that turn out to be anything but. “Some prices go down, but in reality others go up by more at the same time. Customers are being duped,” he says. “For the past ten years we have had huge price cuts every January and yet every year the margins end up higher. You’d have to ask them, but can the major supermarkets afford to reduce their margins by 1 or 2 per cent? I don’t think someone like Sainsbury’s could.

“So it becomes all about how do you work on price to give the impression that you are more competitive than you are. Don’t always believe the hype that says ‘Manager’s Special’.”

Waitrose traditionally has shied away from publicity, but Mr Price’s comments reflect a newfound steeliness in the business and its owner, the John Lewis Partnership.

Two months ago, Mr Price spoke out about “Tescoland” and the growing dominance of the big four supermarkets in the UK. He called on the Competition Commission to do something to break the stranglehold and open up the market, prompting a sharp, public rebuke from Tesco.

Just as then, there is an element of self-interest to the 46-year-old’s argument today. He is committed to changing the popular belief that you should consider remortgaging before attempting a weekly shop among the English farmhouse veal escalopes and Greek sea bass fillets on offer at Waitrose.

He insists that the comments about his rivals’ pricing strategies have nothing to do with any personal “axe to grind”. He adds that they are unrelated to the Office of Fair Trading’s investigation into supermarket collusion over milk prices, in which Waitrose was never implicated.

Instead, he insists that his fundamental concern is that, in slugging it out on price, Britain’s biggest supermarkets are changing the perception of what value is all about.

“The British consumer has been duped into thinking value means cheap, but it’s not true,” he says. “I wouldn’t want my children to eat economy burgers made with mechanically recovered meat.”

He argues that Waitrose is 15 per cent cheaper than Marks & Spencer, only 2 per cent more expensive than Sainsbury’s and that, in the vast majority of cases, it is Waitrose customers who receive the higher-quality product.

“Just because we have nice products, nice stores and nice staff doesn’t mean we are expensive,” he says. “Our customers are paying a fair price, an honest price for a quality product. We offer them fantastic value for money.”

He reels off a Christmas menu of examples in an effort to prove his point. He asserts that the gammon sold in a Waitrose is whole muscle, from one piece of meat, and not “formed” out of different pieces, as can be the case at one rival.

He says that the group’s own-label frozen peas are produced to exactly the same specification as opponents’ premium label products, but are classed as standard and priced lower.

However, the decision to hold up the Waitrose Christmas turkey as a further shining illustration of the group’s credentials is unfortunate. A report on Friday revealed that Waitrose would be unable to supply any organic turkeys to its customers for December 25, given the recent bird-flu scare that led to a cull at its two farm suppliers.

Mr Price counters that the 1,300 customers who ordered an organic bird were happy to accept a free-range alternative. He adds that the group did not want to switch to a new organic supplier at the last minute and risk lowering its standards.

He says: “It’s worth mentioning that 80 per cent of those who received our letter telling them what had happened – so 1,000 people – sent back the £10 voucher we gave them and asked us to give it to the farmer instead. Now that’s a real goodwill-at-Christmas story.”

That Waitrose is causing ripples in the £128 billion supermarket sector is beyond any doubt. Sir Terry Leahy, the chief executive of Tesco, told analysts last week that Britain’s biggest supermarket group had taken share from every rival “bar Waitrose” in recent months.

Waitrose has doubled in size since the end of the 1990s and now runs 187 supermarkets across the UK catering for a total of four million shoppers a week. Profits at the half-year stage were up 29.7 per cent at £140 million on a turnover of £1.9 billion, and sales in the year to date are up 6.8 per cent.

Waitrose holds a 4 per cent share of the grocery market and is Britain’s sixth-biggest chain, but it commands 10 per cent of all fish sold in the UK and holds an 18 per cent share of the organic trade.

Mr Price adds that the fastest-growing part of the market is premium food, which has forced the big four to “move on to our patch” at the same time as ensuring that they compete with discounters, such as Aldi and Lidl.

He reiterates that the masterplan for Waitrose is to double in size again over the next decade in a move that is likely to see it become far more flexible over the type of formats that it operates.

It has already opened a food hall in the John Lewis store in Oxford Street, showcasing such products as cave-aged Emmental cheese and Australian rock lobster.

Waitrose will also consider a move into both smaller convenience-store-sized outlets as well as hypermarkets under the expansion drive.

It runs a 6,000 sq ft (560 sq m) store in Blaby, Leicestershire, less than half the size of its traditional supermarkets. “I want to study and understand the opportunities,” Mr Price says.

Further growth will come online, both through its own website and through Ocado, the popular internet shopping business in which Waitrose owns a 30 per cent stake.

The outcome of the Competition Commission’s continuing inquiry into supermarket competition will be key to determining the potential for Waitrose. Three years ago it benefited from the regulator’s inquiry into the Morrison-Safeway merger when it picked up 19 former Safeway stores that Wm Morrison was forced to sell. A handful became the first Waitrose stores in the North of England.

Mr Price does not expect forced disposals when the present Competition Commission investigation is completed early next year. However, he advocates that the regulator stick to the proposals that could force rivals to sell off land, as well as ending the practice of forcing councils into exclusivity agreements in an attempt to block out the competition.

He says: “In 1986 the top four supermarkets had 35 per cent of the market. In 2007 it’s 75 per cent. I’ve already said if things are left unchecked it could one day get to 95 per cent. You have to sit back and ask yourself: ‘Is that a good situation for the UK to find itself in?’ ” His optimism about the prospects for Waitrose is based on a feeling that events are playing into the group’s hands. He argues that Waitrose had always been about being “a good citizen” long before Al Gore came along with An Inconvenient Truth. He adds that more people are realising the link between “quality food and quality of life”. Mr Price makes no secret of being in this camp himself.

Soon after his appointment as managing director he told a newspaper that his promotion marked the revival of the “chubby grocer”. He argues that life’s too short for fitness and instead revels in a three-course meal.

His views are likely to be heard far more in the coming year. “We started to shout more in 1998 when I joined as marketing director,” he says. “In the past ten years we have done a really good job in getting people to understand what we are about.

“We are more than happy to stand up and say these are our views, this is what we believe. There’s simply a real confidence in the business now.”

Curriculum vitae

Born: March 2, 1961, in Crewe
Education: Lancaster University, degree in archaeology
Career: Joined the John Lewis Partnership on a graduate training scheme in 1982. Jobs included managing stores in High Wycombe and Cheadle. Became marketing director for Waitrose in 1998 and director of selling and marketing two years later. In 2005 he was made development director at John Lewis before being appointed managing director of Waitrose in April 2007
Family: Married, with two daughters
Interests: Golf and flyfishing

The leader questioned

If you could change one thing in the financial and commercial environment, what would it be? Changes in the planning regime to allow greater competition for food retailing in the UK

Who is or was your mentor? There have been many influences in my life. However, I would single out my father, for the way he built his business, and also Brian O’Callaghan, a former director of trading at John Lewis Department Stores

Does money motivate you? When it comes to measuring a man’s success, don’t count money, count happiness. I am very happy

What is the most important event to happen in your working life? Moving from John Lewis Department Stores to work at Waitrose in 1998

What gadget must you have? My BlackBerry

What does leadership mean to you? Ensuring that all 38,000 Waitrose partners are motivated to be the very best they can be, and to ensure that Waitrose is the very best it can be

Which business person do you most admire? Anita Roddick, for being single-minded about her beliefs

How do you relax? Going on picnics with my family