Walmart, the world’s biggest retailer, estimates that savings of between 5-15%, or $4bn-$12bn (£2bn-£7.4bn), will be possible by globalising its purchasing.

According to the Financial Times, the move is part of Walmart’s efforts to increase the proportion of goods that it buys direct from manufacturers. Currently it buys less than 20% of its merchandise directly from manufacturers and purchases are generally made on a country by country basis.

The retailer’s long-term goal is to buy 80% of its stock direct and it has already established four global merchandising centres for general goods and clothing, including a centre in the UK for the George brand.

Following a trial in the US, which led to a 10% reduction in purchasing costs of apples, in 2010 Walmart plans to expand combined purchasing of fresh fruit and vegetables for its stores in Canada, the US and Mexico, with other categories under consideration.