Planet Retail pegged Wal-Mart as the world's largest retailer by sales in a list of the 30 market leaders for the tenth year in a row. The US-based company hit sales of US$395.31bn last year, a far cry from the second place; French group Carrefour, with US$137bn.

Wal-Mart had a 6.3 per cent share of the global market in 2006, equal to that of its four largest competitors combined. UK company Tesco climbed to third position at US$99bn, followed by Germany's Metro and Japan's Seven and I.

The top 30 grocery retailers together claimed 31 per cent of the global market, worth around US$21.1 trillion.

According to the report, the major retailers were getting increasing amounts of their revenue from emerging markets, primarily Asia.