Waitrose is to create more than 2,500 jobs this year in the biggest expansion in its history.

The supermarket chain will confirm today that it has agreed to buy 13 stores from the Co-operative Group, for an undisclosed sum, after the latter's takeover of Somerfield. It plans to boost staff numbers at the stores significantly.

In addition, Waitrose will announce that it plans to open at least nine new stores this year, including sites at Bristol, Altrincham, Colchester, Winchester and Weston-super-Mare.

Mark Price, managing director of Waitrose, told The Times: “As a result of this acquisition and our expansion plans, we will be creating 2,250 new jobs in the stores, but there will be more in the distribution, warehouse and call centre operations.”

Mr Price said that all staff recruited, including existing employees of the Somerfield stores involved, would become “partners” at Waitrose - whose staff own the business - entitling them to an annual bonus and a non-contributory final salary pension plan.

Each store bought from the Co-op would, he said, have 150 to 200 staff once converted to the Waitrose format - about twice the number that a comparable Somerfield store would typically employ. This means that about 4,000 people, including staff already working at the stores, will become Waitrose “partners” this year, taking the total above 43,000.

Waitrose has two strategic aims for 2009: to overtake Marks & Spencer in food and drink sales and to take market share from Tesco and Sainsbury's in sales of ingredients and food being bought by family shoppers.

“These two things are within our grasp,” Mr Price said. “In food and drink, we are only just behind M&S at present, but given that we will have 220 stores and they have 1,000 outlets selling food and drink, that will be quite an achievement. We're already ahead of them if you include household goods.

“But we also want to do more for family cooks and in ingredients. We have already made ourselves more competitive in this area - last year we invested £50 million in price and introduced offers on some 700 lines - and feel there is more to do.”

Mr Price said that Waitrose, which is part of the John Lewis Partnership, could even open more than the nine stores it has earmarked. He would not deny that Waitrose is in talks with the administrators of Woolworths to buy some of the crashed variety retailer's former sites.

However, he did deny that everyday products sold at Waitrose were more expensive than at other supermarkets. “Yes, we have 8,000 lines where we are unashamedly trying to offer the best and will charge more, but cornflakes cost the same at Waitrose as they do at Tesco and milk costs the same as it does at Asda.

“People will be surprised, I think, that Waitrose has taken this opportunity to grow so aggressively in this environment. But the best time to go fishing is when the weather's at its worst.”

The Office of Fair Trading said last night that it would not be referring the Co-op's takeover of Somerfield to the Competition Commission, as it was satisfied with Co-op's agreement to sell 133 stores in areas where competition would otherwise have been reduced.

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