The group posted a 1% fall in UK like-for-like sales in its first quarter following a "small but discernible impact" from the horse meat crisis after it was forced to withdraw four products.
Tesco said it was also suffering from continuing woes in its general merchandise division, with the sales slip marking a reversal in recent improvements following a 0.5% bounceback in sales at the end of its financial year.
But the chain insisted its turnaround plans were on track and promised a relaunch of its non-food ranges, starting in smaller stores in the coming months followed by a company-wide overhaul later in the the year.
It added sales of frozen and chilled convenience meals had picked up in recent weeks.
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