An international conference on tobacco control in Uruguay has adopted regulations to restrict or ban flavouring additives that make cigarettes more appealing to new smokers.
Delegates from more than 170 countries have signed a United Nations Tobacco Control Treaty and recommended that tobacco producers should disclose their products' ingredients to national health authorities.
The guidelines represent the latest public health setback for the tobacco industry.
World Health Organization figures point to big losses of life from tobacco use.
It says tobacco kills more people than Aids, legal drugs, illegal drugs, road accidents, murder and suicide combined. It estimates that of the six billion people alive today, half a billion will eventually be killed by tobacco.
It says the industry lobbied hard against the latest measures. The guidelines would now be used by national governments to draw up legislation.