The consumer affairs watchdog said on Friday it suspected cigarette price-fixing involving tobacco companies and retailers, including all big four supermarket chains, between 2000 and 2003.
The Office of Fair Trading (OFT) issued a so-called statement of objections naming two tobacco manufacturers - Imperial Tobacco and Japan Tobacco-owned Gallaher - and 11 retailers.
The retailers are Wal-Mart-owned Asda, Co-operative Group, First Quench, Morrisons, Safeway, Sainsbury, Shell, Somerfield, T&S Stores, Tesco and TM Retail.
Imperial Tobacco had no immediate comment. Gallaher, which is owned by Japan Tobacco, could not immediately be reached for comment.
The OFT made two allegations, including that there were arrangements between "each manufacturer and each retailer that restricted the ability of each of these retailers to determine its selling prices independently, by linking the retail price of a manufacturer's brand to the retail price of a competing brand of another manufacturer".
The second was more specific, alleging "in the case of Gallaher, Imperial Tobacco, Asda, Sainsbury, Shell, Somerfield and Tesco, the indirect exchange of proposed future retail prices between competitors".
The allegations come two days after the OFT was forced to apologise to supermarket Morrisons and pay 100,000 pounds to settle a defamation action over an incorrect accusation in another antitrust probe.
