Wal Mart, like its competitors Tesco and Carrefour, may be making huge strides in Asia but the actions of the US giant within its own borders are beginning to raise some eyebrows.

Certain sections of the US press, most notably the New York Times, have recently reported the world's largest retailer has spent a proportion of last year's $11bn profits spying on its critics and, most disturbingly, its own employees. According to the NY Times, a Wal-Mart employee recently admitted to recording a conversation between a reporter with the newspaper - Michael Barbaro - and company officials.

Not stopping there, the employee responsible, Bruce Gabbard, then told the Wall Street Journal the department he worked for spied on critics of the company. Unsurprisingly Wal Mart issued a swift apology and used their considerable clout to prevent Mr Gabbard from giving any further gems to the hungry Big Apple press corps.

What this means for a company whose share price has recently plummeted nearly $20 since the current chairman of the company, H.Lee Scott Jnr, took over from David Glass in January 2000, remains to be seen. But whilst the company continues to grow its base in Asia and beyond, it seems the leader of the retail revolution needs to work fast to convince the US public and shareholders that their hard-earned squeaky-clean image is still deserved.