Warm weather and sales of goods related to the World Cup underpinned a strong rise in first-quarter sales at supermarket operator J. Sainsbury PLC.

Sainsbury's, Britain's third-largest grocery chain, said Wednesday that same-store sales, excluding petrol, rose 5.7 percent in the 12 weeks to June 17.

Trolleys are lined up at a Sainsbury's store in west London, March 29, 2006. The third largest supermarket in Britain today announced a rise in first quarter profits for 2006 up by 5.3 per cent. [Reuters]

The company said that several sunny days and soccer fever spurred by the tournament in Germany, which is held every four years, had outweighed a slower post-Easter period.

Chief Executive Justin King, hired in 2004 from Marks & Spencer Group PLC to improve the fortunes of the struggling group, said the sales results were proof his turnaround strategy was paying off.

"This quarter is a good start to the second year of our Making Sainsbury's Great Again plan," King said in a trading update to the London Stock Exchange.

"We are now providing a much better and more consistent shopping experience," he added. "We have listened to customers and responded to what's important to them."

Sainsbury's has struggled to deal with a price war waged by market leader Tesco PLC and No. 2 Wal-Mart Stores Inc.'s Asda. Supply and distribution problems also left its shelves frequently understocked.

"We've continued our investment in lower prices, raised quality standards and developed new products, and our sales performance continues to reflect the restored confidence customers now have in our ability to deliver great products at fair prices," said King.

Same store sales including petrol were up 7.1 percent in the quarter. Total sales, which also adds in online retailing, rose 8.1 percent.

The latest figures are likely to bring Sainsbury's, which was the country's leading grocer 10 years ago and now has a 16 percent share of the market, closer to Asda's 16.4 percent share. Tesco remains way out in front with a massive 31.1 percent market share.

However, shares in Sainsbury's dropped 0.6 percent to 321 pence (US$5.92; euro4.72) on the London Stock Exchange as analysts warned that the growth rate was unlikely to be sustained. The trading update also neglected to provide news on profit margins and future earnings.

Seymour Pierce retail analyst Richard Ratner said that the sales growth was marginally higher than expected, but he warned that it was unlikely to continue "as fast as some are expecting."

Hargreaves Lansdown Stockbrokers analyst Keith Bowman said that "sooner or later investors will remember that a company's share price is built on earnings, not sales.

"There is no mention of the all-important profits margin in today's statement, and therefore investors would be wise in containing their future expectations."

Along with his optimism on the sales performance, King noted that "going forward we are up against tougher comparatives and the market continues to be very competitive."