The bitter food pricing war between the multiple supermarkets is spilling over into non food with Tesco and Asda slashing prices as they both fight to convince consumers that they are the cheapest supermarket for non food.

In a week where Verdict Research tipped Tesco to become the biggest non food retailer by the end of the year with a 3.6% share of the market, the chain lost its position as the least expensive supermarket in The Grocer's quarterly survey of non food prices.

Its basket of 33 goods in our fifth report was 56p pricier than Asda's, which regained the crown. Asda recorded a price of £171.94 for the non food shopping list, which includes clothing, with Tesco at £172.50, marking a complete turnaround from our last report in May, when Asda trailed Tesco by 62p.

The fierce battle for the non food title between Tesco and Asda meant that both retailers have slashed prices heavily since our last report. Asda's basket came in £6.49 cheaper than May's list, while Tesco's cost £5.31 less than last time. Both were well ahead of third placed Sainsbury's total of £219.46 - a massive £47.52 more expensive than Asda.

Non food is rapidly becoming the key battleground for supermarket chains as they seek to carve out larger market share.

Morrisons, which has lagged behind its rivals in this area, is halfway through the first phase of a non food refurbishment programme and has increased its range to include products such as LCD TVs for the first time.

But even as it does so, Asda has taken non food to a new level with the launch of a furniture catalogue featuring a range of 'fine' lines, such as oak dining furniture and leather sofas. It has also added a 137-item flat-pack furniture range to its offer this week. Crucially, the ­catalogue launch comes ahead of Tesco's unveiling of a non food catalogue, which is expected to be announced next month.

In The Grocer survey Asda was also the cheapest supermarket when excluding clothes, coming in at £155.19. Tesco was close behind at £155.75, while Sainsbury's was third at £179.86 and Morrisons fourth at £188.11.

A spokeswoman for Asda said: "Tesco might be the biggest, but we're thrilled that Asda is still leading the way when it comes to value. We've always led from the front when it comes to non food in supermarkets. We were the first to launch a fashion brand, the first to offer electrical ranges and the first to open superstores selling only non food products. We have a fraction of the number of stores of our competitors, so while we may not be the biggest, we're certainly the most innovative."

In a double victory, Asda also emerged as the cheapest online supermarket retailer in The Grocer 33's latest internet shopping survey. Its basket came in at a cost of £46.97 compared to Sainsbury's in second place at £50.37. Tesco was the most expensive at £50.89, largely due to its £5.99 delivery charge and promotions on Jacob's Creek Chardonnay at rival stores - including the knock-down price of £2.99 at Ocado.

However, Waitrose was declared our star performer this quarter, thanks to the delivery of all 33 items and the most positive online ordering experience.