The food and grocery market will be worth £170 billion in five years, according to retail analysts IGD.

The sector is set to grow at an average of 4 per cent a year from its current value of£140 billion.

Growth in online and discount retailing will outpace the market, with the value of online food and grocery set to nearly double by 2013 from£3.2 billion to£6.2 billion, IGD said in a survey released today.

The value of the discounters will grow from£5.5 billion to£8.5 billion, and market share will rise from 3.9 per cent to 5 per cent.

IGD chief executive Joanne Denney-Finch said the online grocery market is benefitting from faster home broadband connections and growing customer familiarity with shopping online.

She added: “The major retailers are focusing on developing the online channel and making the shopping experience easier and more flexible.”

Denney-Finch said the discounters "look set to continue growing ahead of the market, although the pace of growth will slow as the major retailers continue to develop their own value offers in response”.