Tesco has reported a 1.5% decrease in like-for-like sales, according to the latest figures.Published in its third-quarter interim management statement, Tesco has blamed a “weaker grocery market” for the decline.The fall in like-for-like sales exclude both VAT and petrol. Total sales in the UK, including VAT and excluding petrol, increased by 0.9%.It also said that international conditions remain challenging, particularly in Thailand and Ireland. Elsewhere, in Poland and Turkey, the company is seeing better trends.Group sales for the 13 weeks ending 23 November 2013 increased by 0.6% at actual exchange rates and by 0.2% at constant rates, excluding petrol. Including petrol, group sales decreased by 0.8% at actual exchange rates and by 1.2% at constant rates.Philip Clarke, chief executive, added that the group’s decision to “significantly reduce the amount of new space” it opens has also held back sales performance in the short-term. “Customers are continuing to respond positively to the changes we are making to the UK business to differentiate our offer and position Tesco as a multichannel leader,” he said. “These include the re-launch of Tesco Finest, over 100 more store refreshes in the quarter and further investment into our fast-growing online grocery service.” Clarke concluded that Tesco is confident that its strategic priorities, including strengthening the UK business and ensuring capital discipline, will “drive long-term value and returns”.In a statement, Tesco said that “despite the challenging conditions in many of our markets, we are performing in line with market expectations for the full year”.