The World Health Organization (WHO) on Thursday urged governments to treat e-cigarettes similarly to tobacco and ban all flavours, threatening cigarette companies’ bets on smoking alternatives.

Some researchers, campaigners and governments see e-cigarettes, or vapes, as a key tool in reducing the death and disease caused by smoking. But the U.N. agency said “urgent measures” were needed to control them.

Citing studies, it said there was insufficient evidence that vapes helped smokers quit, that they were harmful to health and that they could drive nicotine addiction among non-smokers, especially children and young people.

More 13-15 year olds are using vapes than adults in all WHO regions helped by aggressive marketing, it continued.

“Kids are being recruited and trapped at an early age to use e-cigarettes and may get hooked to nicotine,” said Tedros Adhanom Ghebreyesus, WHO Director-General, urging countries to implement strict measures.

The WHO called for changes, including bans on all flavouring agents like menthol, and the application of tobacco control measures to vapes. Those include high taxes and bans on use in public places.

The WHO has no authority over national regulations and only provides guidance. But its recommendations are often adopted voluntarily.

The WHO and some other anti-tobacco organisations are pushing for stricter regulations on newer nicotine products, aiming for the alternatives on which some cigarette giants like Philip Morris International (PM.N) and British American Tobacco (BATS.L) are basing their future strategies.

Industry players like Imperial Tobacco (IMB.L) and the UK Vaping Industry Association said vapes pose significantly lower health risks than tobacco and help reduce its harms, while flavours are key in encouraging smokers to switch - a position shared by some tobacco control advocates.

Cancer Research UK, for example, says that while e-cigarettes are not risk-free and should only be used to stop smoking, there is no good evidence they cause cancer, whereas smoking causes at least 15 different kinds.

“Regulating vapes like cigarettes would only serve to reinforce misunderstandings about the relative risks of vaping and send the wrong message to smokers,” said Marina Murphy, senior director of scientific and medical affairs at vaping firm ANDS, adding the WHO’s position was “detached from reality”.

The WHO said while long-term health risks were not understood, vapes generated some substances known to cause cancer, posed risks to heart and lung health and could affect brain development in young people.