Sainsbury sales will put pressure on rivals Tesco, Britain's biggest retailer, reported a 1pc drop in like-for-like sales when it updated the market last week and the chief executive, Philip Clarke, warned that his £1bn turnaround plan is taking time to take effect. In contrast, the City expects Sainsbury's to report its 34th consecutive quarter of like-for-like sales growth under the chief executive, Justin King, on Wednesday. Analysts at Sainsbury's house broker, Morgan Stanley, have forecast that Sainsbury's will say like-for-like sales increased 0.6pc in the 12 weeks to June 8, although some analysts believe sales may have grown by as much as 3.5pc. Growth of 0.6pc would be Sainsbury's slowest for more than three years. But Edouard Aubin, analyst at Morgan Stanley, said it would still be an outperformance of listed rivals and that the slowdown was due to the Queen's Diamond Jubilee and an extra bank holiday falling in the same period in 2012. He said: "While Q1 will likely mark Sainsbury's softest like-for-like sales growth in over three years, we note that, unlike listed competitors Tesco and Morrisons, Sainsbury's like-for-like sales remain in positive territory and that, quarter to date, Sainsbury's has continued to gain market share. Additionally, we note that Sainsbury's outperformance was achieved despite limited promotional activity during the quarter. Mr King, who has denied speculation that he is preparing to step down, has revitalised Sainsbury's since taking charge in 2004. The retailer is enjoying particularly strong growth in non-food products, its Tu clothing range and own-brand food ranges. It is also expanding its convenience store business Sainsbury's Local by opening 50 new stores in London and the South East this year.