Supermarket giant Sainsbury's grew like for like sales by slightly less than expected during the fourth quarter following a widely-predicted slowdown since Christmas.Like for like sales excluding fuel but including VAT rose 1% in the 10 weeks to 19 March compared with 3.6% in the third quarter and the 1.5% predicted by analysts at Nomura.Britain's number three grocer increased like for like sales by 4.2% including fuel, giving a full-year increase of 4.7%. Total sales for the quarter increased 6.8% and 3.5% without fuel. The number of customer transactions per week jumped by 1 million year in year to 21 million.Chief executive Justin King said higher sales were driven by demand for its cheap petrol and growth in non-food sales at over three times the rate of food. TV fashion guru Gok Wan is designing womenswear collections for the firm. Gross space growth for the year of 8.5% and 15.9% in the two years to March beat the food chain's target of 15% it set in 2009. "We expect the consumer environment to remain tough, with our customers facing fuel price inflation, uncertain employment prospects and government spending cuts," King said."We have demonstrated our ability to perform well in these conditions and are confident that our growth plans and universal customer appeal, supported by Nectar and coupon at till, mean we are well-positioned for further growth in 2011/12."Final results are out on 11 May.