29/07/2014 10:21 BST | Updated 29/07/2014 10:59 BST

Tesco Supermarket Suffers Worst Sales Decline In At Least 20 Years

PAUL ELLIS via Getty Images
(FILES) In this file picture taken on March 5, 2012 people carry shopping bags through the carpark of a Tesco Extra supermarket in Birkenhead, north-west England. Britain's biggest retailer, supermarket Tesco, looked on course to withdraw from its struggling US business Fresh & Easy as chief executive Philip Clarke on December 5, 2012 said its presence would likely end. AFP PHOTO / PAUL ELLIS (Photo credit should read PAUL ELLIS/AFP/Getty Images)

Britain's biggest retailer Tesco has suffered its worst sales decline in at least two decades as discount rivals continue to attract more customers.

The supermarket giant's sales fell 3.8%, according to the latest till-roll figures from research body Kantar Worldpanel, the biggest decline since it began comparable records in 1994. This meant that the chain's market share fell to 28.9% from 30.3% a year ago.

The latest news sheds light on the tough position Tesco finds itself in, as the supermarket's chief executive Philip Clarke announced he would step down in October after the retailer revealed its worst trading figures in 40 years.

See also:

Will Tesco Chief Philip Clarke's Departure Save The Supermarket?

Tesco Shareholders Slam Bosses' 'Madness' Amid Declining Fortunes

Sainsbury's Sales Fall Again, But By Less Than Rival Supermarket Tesco

Tesco Supermarket Suffers Credit Downgrade After 'Weak' Sales

Ex-Tesco Chief Sir Terry Leahy 'Disappointed' With Supermarket's Decline

The retail giant announced its second profit warning in two years after it said trading was "more challenging than we anticipated", as Clarke was forced to resign due to his failure to turn around the business' ailing fortunes.

According to Kantar, discount supermarkets Aldi and Lidl saw their market shares over over the year to record levels of 4.8% and 3.6% respectively as they enjoyed unprecedented trading. Lidl was itself helped by a 19.5% jump in sales.

Meanwhile, big four supermarket Morrisons saw its sales slide by 3.8% in the 12 weeks ending July 20, seeing its market share slip to 11% from 11.5%.

Sainsbury's sales grew 1.2% to keep its market share at 16.6%, while Asda's market share stayed at 17% as its sales grew by 0.9%.

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