The star-studded RED charity campaign was said last night to have raised just £9 million to fight Aids, tuberculosis and malaria - despite a £52 million marketing drive.

The huge gap between the figures brought concerns that the major brands involved are benefiting more than the charities they are meant to be helping.

RED was launched by rock star Bono in January last year as a ground-breaking bid to commercialise the fight against disease.

It is a huge enterprise involving clothes, sunglasses, credit cards, iPods and mobile phones.

Steven Spielberg has featured in billboard advertisements while model Christy Turlington and actress Scarlett Johansson starred in magazine ads. Bono was seen cruising Chicago's Michigan Avenue with Oprah Winfrey, snapping up RED products.

Firms such as Gap have spent millions advertising and marketing RED design T-shirts and other products. American Express has issued a RED credit card and a RED Motorola phone is also available.

A proportion of all sale proceeds goes to fight disease in the Third World.

But U.S. industry sources suggest the amount raised so far is less than £9 million, while even RED admits it is under £12 million.

Now questions about the progress of the effort have appeared in the magazine Advertising Age.

Mark Rosenman, a public service professor at the Union Institute & University in Cincinnati, told the magazine there are fears that global brands are using the cloak of supporting charity as a marketing tool.

He said: "There is broadening concern that business is taking on the patina of philanthropy and crowding out philanthropic activity, even substituting for it. It benefits the for-profit partners much more than the charitable causes."

Trent Stamp of Charity Navigator, which rates the spending practices of 5,000 non-profit organisations in the U.S., said the jury was still out.

He said: "The RED campaign can be a good start or it can be a colossal waste of money.

"It all depends on whether this edgy, innovative campaign inspires young people to be better citizens or just gives them an excuse to feel good while they buy an overpriced item they don't really need."

RED aims to raise tens of millions over many years to support the Global Fund to Fight Aids, TB and Malaria.

Launching it, Bono warned that the world was losing the fight against HIV/Aids, with 6,500 people dying every day.

He said it was time to use the power of commerce rather than simple philanthropy.

The U2 singer said he had turned to "corporate winners" so the Global Fund could make money "in the slipstream".

Last night a spokesman for RED in Britain said marketing spending here has been minimal but the money raised has been substantial.

She said the figure of 100 million dollars on marketing in the U.S. was only approximate and was money the companies would have been spending anyway.

RED chief executive Bobby Shriver said there had been relatively few products available under the brand until October.

He said that if the project donates £12.5million to the Global Fund in its first year that will be five times the amount given by the private sector in four years.

The director of the Global Fund, Professor Sir Richard Feachem, said he was disappointed and surprised by the criticism.

He said: "RED is a revolutionary concept and represents a real breakthrough in the way businesses contribute.

"As the world's largest funder of Aids, tuberculosis and malaria programmes, the Global Fund cannot depend on traditional fundraising and ad hoc philanthropic contributions. We need our partners to make significant, sustainable commitments, and RED enables businesses to do that.

"By tapping into marketing budgets and consumer spending, it is expanding the of resources channelled to the fight against Aids."

Bono has forged a formidable reputation in the business world.

Last year his New York-based company Partners paid a reported £150 million for a 40 per cent stake in Forbes, the magazine dedicated to celebrating wealth.

U2, who have a £460 million fortune, were also at the centre of a tax avoidance row in the Irish republic in December after moving their music publishing business offshore.