In a statement, Belgian brewer Interbrew noted the speculation in the press. It said that it had undertaken a preliminary analysis, but "that no approach had been made on the matter".
Shares in the Brussels-listed Interbrew fell this morning, trading down 4.25% to €28.15. SAB shares soared by 8.87% to trade at 480p.
A merger between Belgian company Interbrew, owner of the Stella Artois, Hoegaarden and Beck's brands, and SAB, which makes Pilsner Urquell and Amstel, would likely lead to a spate of rival mergers in the industry.
In the Financial Times, it is reported that an offer could be made as early as December 3, with a figure of more than £4bn being mooted.
If the merger did go ahead, the only bigger brewer in the world, by volume of beer produced, would be Anheuser-Busch, owner of the Budweiser brand.
SAB owns and operates 85 breweries in 22 countries, employing more than 31,000 people, and was listed on the London Stock Exchange in 1999. Interbrew is in the process of selling its Carling lager brand, after its takeover of Bass Brewers, in order to meet UK competition regulations.
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