Greggs, the high street bakery chain, said like-for-like sales in the second half of the year so far had only increased by 0.2%, hampered by the "unseasonably mild and wet weather" in September and October.

Sir Michael Darrington, the managing director, said full-year results would depend on the group's performance in the remaining nine weeks of the second half, "and particularly over the Christmas period".

Greggs posted a 20% fall in first-half pre-tax profit, but Sir Michael said: "We continue to believe that performance in the second half will be closer to that of the comparable period last year than was the case in the first half."

Analysts at Numis Securities warned the company still had a lot to do to hit market forecasts for the year.

"As we have said before, there are some substantial risks for Greggs, mainly due to the increased competition from Tesco Express/Metro, Sainsbury's Local, as well as sandwich and coffee bar operators. It also has to face up to consumers' demands for healthier food products."

The group has launched a Healthier Options range, and Sir Michael said consumer reaction had been "encouraging." He added the next phase of the range would be rolled out early in the New Year.

Shares in the group fell 62p to £41.50.

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