White is the new light, and smooth the new mild. Faced with an EU ban on promoting cigarettes with the words low-tar, mild or light from next week, tobacco companies are rebranding their products with a range of new names.

The EU directive was designed to stop the tobacco industry from implying some brands were milder than full- strength versions, when research has shown they deliver just as much tar and cancer-causing toxins.

But the companies are planning to beat the ban by using new names, which market research has shown are still associated with healthier and more "pure" products. Marlboro Lights, one of the bestselling of the "low-tar" brands, will become Marlboro Gold, while Silk Cut Ultra will be known as Silk Cut Smooth.

Camel Ultra Lights will re-emerge as Camel Smooth, and Embassy Mild becomes Embassy Blue.

The circumventing of the ban with subtle marketing and rebranding has outraged the Government and cancer charities, causing them to join forces and launch a full-frontal assault on low-tar cigarettes.

The Department of Health has funded a £2.5m advertising campaign, drawn up by Cancer Research UK, which tackles the tobacco industry head on for the first time.

The TV, radio and press campaign, which starts tomorrow, aims to raise people's awareness of the dangers of low-tar products, and how the tobacco industry is misleading smokers. It is the first time Cancer Research has been involved in an anti-smoking campaign, and marks a departure from the "smoking kills" messages of the past.

The campaign uses the warning "Death Repackaged" to drive home the message that low-tar cigarettes are still deadly.

Professor Gerald Hastings, director of the Centre for Tobacco Control Research at the charity, said: "This campaign marks a step change in that we are telling people about the realities of low-tar cigarettes. For the first time we have a campaign which focuses on the real villain of the piece - the tobacco industry.

"You would have thought the whole issue of health and smoking would have been a problem for them, but with clever, subtle marketing of the mild products, they have turned it into an opportunity, which is pretty despicable,"

More than a third of smokers now favour the light and low-tar brands, which have been particularly marketed at young women.

The tobacco industry has claimed it has never told smokers low-tar brands are safer, but documents released by Cancer Research yesterday showed how they have been marketed in a "health conscious" way. An advertising brief on low-tar brands for Gallaher, the maker of Silk Cut, reads: "The core low-tar smoker is female, upmarket, aged 25-plus, a smart, health- conscious professional who feels guilty about smoking but either doesn't want to give up or can't. Although racked with guilt, they feel reassured that in smoking low-tar they are making a smart choice and will jump at any chance to make themselves feel better about their habit."

The content of cigarettes is measured by government regulators, using a machine that "smokes" products to see how much tar is inhaled.

Scientists say the machine is not accurate, because people inhale the low-tar products in a different way.

Professor Martin Jarvis, from the Health Behaviour Unit at University College London, said: "Low-tar products have ventilation holes on the filter, which mean that when the machine smokes them the tar intake is lower.

"But when humans smoke them, they cover the holes with their fingers, either consciously or sub-consciously, so they are taking in just as much tar and cancer-causing toxins."