Independent retailers were given more bad news this week as TNS Worldpanel data showed sales in the sector dipped 2.2% year-on-year in the 12 weeks to

2 December.

Total grocery sales through independents were £506.6m in the period compared with £517.8m last year. Sales through symbol retailers rose 2.3% to £180.3m, but those through unaffiliated independents were down 4.5% to £326.2m.

Independent retailers' share of the grocery market fell from 2.7% to 2.5%.

Sales though the major supermarket chains rose 5.5% to £18.7bn in the period, according to TNS.

The multiples commanded a 93.1% share of the grocery market during the 12 weeks, compared with 92.8% for the same period in 2006.

The new data is another blow for the independent sector, which is already reeling from the Competition Commission's groceries inquiry verdict that c-store numbers are not in decline in the face of competition from the multiples.

Association of Convenience Stores chief executive James Lowman said the figures painted a "worrying" picture.

On Wednesday the ACS and the Federation of Wholesale Distributors met the Competition Commission's groceries inquiry team to discuss its provisional findings and the remedies it has proposed to increase competition in the market.

Lowman said he was still hopeful of persuading the commission to change its mind over the health of the c-store sector before it published its final report in March.

"We had a frank exchange of views over the full range of issues," said Lowman. "We were encouraged by the noises being made by the commission, particularly in terms of store numbers, and are hopeful we can resolve this issue."

The ACS has clashed with the commission recently over the inquiry's view of the convenience sector. The ACS believes data used by the commission from Experian Goad and the Office of National Statistics, both of which indicate that the number of independent shops is growing, are not fit for purpose because they do not look at the entire market.