Shares in Brambles, the world’s largest pallet supplier, fell by close to 18 per cent at one stage on Friday after the Australian group said that Wal-Mart would make changes to its relationship with pallet suppliers.

Mike Ihlein, chief executive, issued a clarifying statement after the “dramatic over-reaction” in the shares when he pointed out that Brambles’ Chep unit did not generate sales revenue from Wal-Mart itself. Chep manages the picking up and sorting of pallets at many of the retailer’s locations in the US.