Procter & Gamble began what it described as a “takeover” of Asda stores today as part of a joint sustainability campaign to provide clean drinking water in developing countries, claiming the backing in store is “bigger than for the Olympics”.

The company ran a massive point-of-sale blitz to support its sponsorship of the Games but said this would be dwarfed by the scale of support for the new campaign, which includes on-pack marketing, and banners throughout the store and on Asda vans.

Its entire range of more than 1,200 P&G SKUs are included in the partnership, with P&G pledging to provide purifying equipment to make two litres of safe water in developing countries for each product sold between today and 8 May.

A range of products, including Ariel, Gillette and Oral B brands, will continue the campaign for several months.

“This will be at least as big as the support for the Olympics, if not bigger,” said Irwin Lee, managing director of P&G UK and Ireland, who said the campaign would continue the use of P&G’s brand names in its marketing, which was pioneered at London 2012.

A multimillion-pound ad campaign will run on mainstream commercial channels including ITV, Sky2, E4 and Film Four.

Asda stores sell around 3.5 million units of P&G products per week.