Retailers should co-operate more on environmental issues and spend less time trying to out-green each

other, according to Waitrose MD Steven Esom.

Esom said issues such as food miles should be tackled as an industry rather than independently by supermarket chains. "As an industry, we've got to be very careful not to go into greenwash. Care for the environment and our place in society is far more important than grabbing a headline.

"It's only through concerted co-operative action that we will make a change. As an industry, we must work together to ensure that food production and retailing are done in a sustainable and environmentally aware way."