A labour relations storm has blown up at a Coke bottler in Southern California after a driver and union activist was said to have been sacked for drinking the rival brand, Pepsi.

Rick Bronson, who works for Coca-Cola Bottling Co., part of Coca-Cola Enterprises (CCE), in Sylmar, California, was, according to his union, the International Brotherhood of Teamsters, dismissed on June 12 for violating the company's rules prohibiting slander of Coke products. The union alleges that he was actually fired for organising labour campaigns and has filed charges against CCE accusing it of unfair labour practices.

A Coca-Cola Bottling Co. spokesman would not comment on the specific detail of the Bronson case and would not clarify whether drinking competitors' products was a disciplinary offence for the company's employees.