Fashion retailer Next has warned that it will have to lower its profits guidance for this year if the Indian summer continues throughout October.

September is an important month for the industry but, with slower demand for jumpers and coats, Next's sales are currently up 6% in the quarter to the end of October, rather than the 10% previously forecast for the period.

It hopes that it will recover some of the lost sales when the weather turns but if the unusually warm conditions continue for the full duration of October it is likely to lower its full-year profit guidance of £775 million to £815 million.

The group, which overtook Marks & Spencer with a £695 million annual profits haul earlier this year, had been experiencing its strongest sales growth for many years prior to the slower performance seen in September.

Next shares opened 5% lower, while other retailers were also impacted by the update. Marks & Spencer dropped 4% and Sports Direct International fell 1%.