French competition authorities are investigating allegations of price-fixing on household cleaning products at Unilever and Reckitt Benckiser.

The home product makers are among nine international businesses caught up in a cartel investigation, which examines increases in prices apparently agreed between the companies in 2005.

Others whose activities are being examined include Colgate Palmolive, SC Johnson, Henkel, Vendome, Procter & Gamble, Bolton and Sara Lee.

Unilever, whose brands include Cif cream cleaner and Domestos bleach, confirmed that it was co-operating with the French authorities over the investigation that began last year.

However, a spokesman for the consumer goods group said that it had still not received specific details of the allegations.

SC Johnson, the US maker of Pledge furniture polish and Glade air fresheners, is understood to have tipped off the French authorities, according to Le Figaro newspaper.

If found guilty, the companies risk fines of up to 10 per cent of their global sales.

Separately, it has emerged that Unilever is considering appealing its share of a £28 million fine that was imposed in Germany last month over allegations that it took part in a pricing cartel there.

The German antitrust watchdog fined Unilever, Henkel, of Germany, and Sara Lee, of the US, €37 million (£28 million) for fixing the prices of products and illegally passing on information on price talks with retailers.

The watchdog said that the companies agreed to raise prices on dish detergents, toothpastes and shower gels by 5 per cent in early 2006.

Reckitt Benckiser could not be reached for comment.

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