Industry sources said Rhodia's top executives were last night finalising details of its offer with its bankers, and an announcement could come as early as today.
The sources said Rhodia, advised by NM Rothschild and Warburg Dillon Read, was likely to pitch its cash counterbid at around 150p per share, a 13 per cent premium to Albemarle's 130p offer. A&W shares closed 2.5p down at 140p.
The Paris-based group, majority-owned by the French drug company Rhone- Poulenc, is hoping that the counter-offer will be enough to sway Phillips & Drew, A&W's largest shareholder. The fund manager, which has a stake of about 24 per cent, last week refused to accept Albemarle's offer despite a recommendation from A&W, where Paul Rocheleau is chief executive.
P&D believes that the US group is not paying enough for A&W, a leading producer of chemicals for detergents and carbonated drinks with yearly sales of over pounds 815m.
The company's sales and share price have been hit hard by the downturn in chemical markets and the strength of sterling, and a number of shareholders and analysts consider Albemarle's offer too low.
P&D's stance was followed by M&G, which has a stake of over 5 per cent. However, Albemarle secured the support of Mercury Asset Management, the UK group's third-largest investor with a 12 per cent stake.
A bid by Rhodia, which last year had sales of over 5.5bn euros (pounds 3.3bn), would not surprise City analysts. The French company has been seen as a possible bidder for A&W since last week when it revealed that it had held preliminary talks with the British company.
Industry experts believe that a link between Rhodia and A&W would yield greater cost savings as both companies produce phosphates for the cleaning and drinks industries.
A Rhodia counteroffer could open the way for other bids, with the US group FMC and a private UK company backed by venture capitalist CVC tipped as potential bidders.