Maria Cheng / The Associated Press

LONDON — Britain will start regulating electronic cigarettes and other products containing nicotine as medicines, according to the country’s top regulator.

In a statement on Wednesday, the Medicines and Health Regulatory Agency said it would treat e-cigarettes as medicines “so that people using these products have the confidence they are safe, are of the right quality and work.” E-cigarettes are battery-operated products that turn nicotine into a vapor that is inhaled by the user.

“While it’s best to quit completely, I realize that not every smoker can, and it is much better to get nicotine from safer sources such as nicotine-replacement therapy,” said Britain’s Chief Medical Officer Sally Davies in a statement. “It’s only right (e-cigarettes) are properly regulated to be safe and work effectively.” Cigarettes are exempt from the regulation.

Last week, Britain’s independent health watchdog said smokers unable to go cold turkey should be encouraged to use nicotine products like gum and patches to help them cut down. It hadn’t recommended e-cigarettes because they weren’t yet regulated. Experts say smokers are at risk from the toxins and tar in cigarettes, not the nicotine.

Smoking is the biggest cause of preventable deaths in England, killing about 80,000 people every year.

In the U.S., the Food and Drug Administration announced in 2011 that it would regulate e-cigarettes as tobacco products and won’t try to regulate them under stricter rules for drug-delivery devices following a legal battle. The FDA plans to assert regulatory authority over the fast-growing category in the near future.