The UK‘s largest grocers were out-performed by lower & higher priced competitors over recent weeks, new research out today shows.

According to research firm Kantar Worldpanel, market leader Tesco saw its share of the grocery sector drop in the 12 weeks to April 17th 2012 down from 30.9 per cent a year earlier to 30.7 per cent, as it‘s till roll sales increased 4.2 per cent year-on-year.

Closest competitors Asda & Sainsbury‘s, which now have shares of 17.6 per cent and 16.6 per cent respectively, out-performed Tesco in terms of sales, with the latter particularly impressing with an increase in trading value of 5.4 per cent.

It was those retailers operating at both the premium and budget end of the grocery sector that saw the greatest growth however, with Waitrose, Aldi, Lidl & Iceland all increasing their market share.

Edward Garner, director at Kantar Worldpanel, explains: “The discounters and Waitrose are outperforming the middle ground as shoppers polarise their spend.

“To this effect, Aldi and Lidl continue their strong run and both achieve record shares this period. Iceland‘s growth rate of 9.1 per cent is also racing ahead of the market – further proof that consumers are convinced by strong value-for-money messages.”

The overall market rose by five per cent in terms of sales value over the three months but most of this growth was due to high food inflation which Kantar estimates at 5.5 per cent.

Of the big four companies in the market, Tesco and Morrisons had the weakest period as they both saw their shares of the market drop 0.2 per cent, however for Tesco this represented an improvement on recent results.

Along with increasing its market share by 0.2 per cent in the period, Waitrose also saw a strong nine per cent jump in sales values, and Garner believes that this underlines a growing consumer trend for choosing quality products.

“Waitrose sees no slowdown in its growth as some households refuse to let economic pressures affect their food purchasing,” Garner added.

“This may also be a result of cutbacks on eating out which have meant that some shoppers are willing to spend more money on bringing the dining out experience into the home.

“The continued growth of premium own-labels, particularly Tesco Finest and Sainsbury‘s Taste the Difference, is further evidence of this behaviour.”