Two supermarket chains are still using more plastic bags to deliver groceries, after pledging to cut their use of them, according to a recent survey. The Grocer found that Sainsburys used 11 bags to pack 33 items, five more bags more than in the last survey conducted three months ago. Asdas used 15 bags for 32 items, up from 14 bags for 33 items in the last survey. However, other supermarket chains have reduced the number of bags they use to deliver groceries to online customers. The survey found that to deliver 33 products, Tesco used just four bags and Waitrose used just five. A British Retail Consortium (BRC) spokesman said: Some retailers, including not just supermarkets, are committed to reducing the amount of plastic bags they use by 25% by the end of next year. They are committing themselves in three major ways: one, to create incentives for customers to re-use bags, two, to reduce the amount of materials used in the bags and three, to recycle the bags. Waste Watch senior consultant Mike Webster said the nine biggest supermarket chains give out more than 17 billion plastic bags per year. He urges retailers to look at using alternative methods to giving out bags such as charging customers for them. What the retailers surveyed said, was that some of their staff are unfortunately using more bags than they need to. However, most retailers have addressed the issue and warned their staff to use less bags, said the BRC spokesman.