SABMiller shares have leapt by more than 12% on reports that the brewer might prove the target of a £75bn takeover bid.

The value of the company, which sells beer brands such as Foster's and Coors, surged after the Wall Street Journal said Anheuser-Busch InBev, the owner of Budweiser, was talking to banks about raising finance for an acquisition.

A tie-up between the world's two largest brewers has been rumoured for years, but the speculation has been revived by the surge in international mergers this year. The Journal added that AB InBev was not in active discussions with SABMiller, but was attempting to line up financing before making a formal approach.

The news came after Heineken rejected a takeover offer from SABMiller after the founding family of the Dutch brewer insisted it should remain independent.

In a statement on Monday intended to quell press speculation, Heineken confirmed it had been approached by London-listed SABMiller, the world's second-largest brewer, but said the proposal was "non-actionable".

Brewers: the big three

SAB Miller

Headquarters: London, UK

Brands: Peroni; Grolsch; Miller Lite

Annual revenues: $34bn (£21bn)

Annual profits: $4.8bn

Employees: 70,000

Chief executive: Alan Clark

Anheuser-Busch InBev

Headquarters: Leuven, Belgium

Brands: Budweiser; Stella Artois; Corona

Annual revenues: $43.2bn (£26.6bn)

Annual profits: $18.5bn

Employees: 150,000

Chief executive: Carlos Brito

Heineken

Headquarters: Amsterdam, Netherlands

Brands: Heineken; Amstel; Sol

Annual revenues: €19.2bn (£15.3bn)

Annual profits: €2.1bn

Employees: 85,000

Chief executive: Jean-Francois van Boxmeer