UK food retailer Big Food Group has posted a 14% increase in first-half pre-tax profit, boosted by an improved performance at its Iceland frozen food chain.

The company reported pre-tax profit of £5.6m (US$9.3m), compared to £4.9m a year earlier. Profit before tax, goodwill amortisation and exceptional items rose sharply to £15.9m from £6.6m a year earlier.

Chief executive Bill Grimsey told Dow Jones Newswires that Iceland's improved performance was due to promotions and refurbished stores rather than the hot UK summer.

"The real driver was the new store format and a return to great value deals, rather than the weather," he said. "We sold lots more ice cream and drinks, but sold less pizza."

As well as Iceland, Big Food Group operates the Booker Cash and Carry wholesaler, which has 33% of the cash and carry market, and Woodward Foodservice, which distributes frozen foods to events, pubs, hotels and restaurants.

The group said sales for the six months were almost flat at £2.39bn.