NEW YORK — In a major new effort to curb smoking, a top U.S. health official pledged Thursday to try to ban menthol cigarettes and flavored cigars and tighten rules governing the sale of most flavored versions of electronic cigarettes.

The proposed restrictions were aimed mainly at reducing smoking in kids: About half of teens who smoke cigarettes choose menthols, and flavored e-cigarettes have been blamed for a recent increase in teen vaping rates.

“I will not allow a generation of children to become addicted to nicotine through e-cigarettes,” Scott Gottlieb, commissioner of the Food and Drug Administration, said in a statement.

Health advocates say a menthol ban would have greater impact on the health of Americans, but it would probably take years to put in place. The changes for e-cigarettes could kick in within a few months.

Battery-powered e-cigarettes are more popular among teens than regular smokes and are considered safer. But many versions contain potentially addictive nicotine, and health officials believe they set kids who try them on a path toward regular cigarettes.

Gottlieb called for additional steps to prevent the marketing of e-cigarettes directly to kids and online sales to minors. He also proposed beefing up measures to ensure that convenience stores and some other retailers do not sell e-cigarettes in kid-friendly flavors such as cherry and vanilla. They could still be sold in vape shops or other businesses that do not admit minors.

Smoking is the nation’s leading cause of preventable illness, causing more than 480,000 deaths each year. The FDA currently bans sales of e-cigarettes and tobacco products to those under 18.

In 2009, the government banned a number of kid-friendly flavorings in cigarettes. But after an aggressive lobbying effort by tobacco companies, menthol was exempted.

Gottlieb’s proposal for e-cigarette flavorings also exempts menthol. He said menthol e-cigarettes may be an option for adults who turn to vaping products to quit regular cigarettes, and he decided not to push for an end to menthol flavoring in vaping products.

Smoking has been declining for more than five decades. Some 42 percent of U.S. adults smoked in the early 1960s. Last year, the rate was down to 14 percent, according to the Centers for Disease Control and Prevention.