Britain's best and worst supermarket revealed

Asda has come in last place in a survey by consumer group Which? that ranks supermarkets.

Waitrose took the top spot in the main in-store experience category for the third year running, earning praise for its spacious stores and helpful staff.

Competitor Marks and Spencer came in second, with customers complimenting the company's high-quality products and "great customer service".

But Asda suffered due to a perception that food quality is "average".

Meanwhile, M&S Simply Food came top of the first ever convenience store rankings, scoring almost 10% higher than second-placed Little Waitrose.

The researchers surveyed more than 7,000 people and asked them about their views on supermarkets they had shopped at within the previous six months.

They then compiled an overall score for each firm based on a variety of customer satisfaction measures and the likelihood of recommending the store to a friend.

Iceland topped the online grocery category for the second year in a row based on its convenient delivery slots and value, followed closely by Ocado, which earned plaudits for its quality products and good customer service.

Value for money was also a big consideration for customers this year, as rising inflation and the weakness in the pound begin to put pressure on prices.

Aldi and Lidl were the only two supermarkets on the list to be awarded top marks for value, and grocery giants Tesco (Frankfurt: 852647 - news) and Sainsbury (Amsterdam: SJ6.AS - news) 's scores suffered thanks to low ratings on price.

Richard Headland, Which? magazine editor, said that concerns over rising prices was fuelling even more competition among stores in an already fierce market.

"While value for money remains a top priority, in-store appearance and the availability of quality and fresh products can also go a long way to satisfying shoppers' needs," he said.