New market share figures indicate that Wal-Mart subsidiary Asda has extended its lead on Sainsbury's, the supermarket group it overtook earlier this year.

Figures from Taylor Nelson Sofres show that Sainsbury's overall till roll share eased back to 16.1% in the 12 weeks ended 12 October, down from 17.4% in the year-ago period, while Asda's rose to 16.8% (12 months ago: 16%).

Tesco and Wm Morrison also grew their share of the market, to 27% and 6.3% respectively.

Safeway's share of the market slipped back 0.6% to 9.2%, while Somerfield's improved by 0.2% to 5.6%.