The owner of the warehouse destroyed by a blaze that also tragically killed four firefighters has moved to reassure customers and suppliers.

Family-owned Wealmoor said it had managed to divert business from its Atherstone packhouse in Warwickshire to its main site in Hayes near Heathrow Airport following the fire last week.

The 160,000 sq ft plant had been packing vegetables and exotic fruit for retailers including Tesco, Sainsbury's and Asda.

"Our priority is to do what we can to work with the police and fire service to help establish the cause of the blaze," said a spokesman for the company. He praised the retailers for their support, but admitted they had switched some business to rivals.

"The industry, our customers and suppliers have been incredibly supportive during this difficult time," he said. "Some of our business has been temporarily redirected to other suppliers to reduce the impact on customers and ensure orders are fulfilled."

A Tesco source said the primary concern was with those who had lost their lives, but it was standing by Wealmoor as a supplier.

Wealmoor insisted the fire would not have a big impact on British growers. A few days before the blaze workers had been packing locally grown field vegetables and legumes, but between November and March it switches to imports.

Most of Wealmoor's £62m sales (2006 figures) come from exotic produce, including conventional and organic beans from its own farm in the Gambia, baby corn, sweet potato, mango, paw paw and pineapple.

The fire is a major blow for Wealmoor, which had only bought the site from the administrators of defunct produce giant Bomfords in August. The company had been in the process of completing the installation of a sprinkler system, which may have prevented the fire taking hold.