The new restrictions do not apply to menthol, mint or tobacco flavors, which the F.D.A. wants to keep available for adults who are using e-cigarettes to quit smoking combustible cigarettes.

The F.D.A. will also track youth use of menthol and mint e-cigarettes, Dr. Gottlieb said. If they become too popular, he added, the F.D.A. will reconsider the exemption. Such a move would be especially harmful to Juul Labs. The vaping giant, under F.D.A. pressure, has already moved sales of its flavored e-cigarettes online, except for menthol, mint and tobacco, which it sells in stores.

But some public health advocates say the moves are too late.

“While this announcement sounds big and bold, it isn’t really,” said Micah Berman, an associate professor at The Ohio State University College of Public Health and Moritz College of Law. “The F.D.A.’s announcement exempts mint/menthol, which is the most popular flavor with kids and one that makes it easier to initiate use. And in any event, most kids are getting these products online or through older friends, not buying them in convenience stores.”

The proposal also calls for banning the sale of many flavored cigars.

“The data also indicate that eliminating flavors from cigars would likely help prevent cigar initiation by young people,” Dr. Gottlieb said. Under the new plan, cigar companies would have 30 days to remove the products from the market, and would have to apply for F.D.A. approval to go back on the shelves.

In addition, all e-cigarettes, cigars and related products not on the market by Feb. 15, 2007, must seek F.D.A. approval to sell them by August 2021. As part of their application, manufacturers must prove that their products are beneficial to public health. The agency’s original deadline for these products to comply with new, tougher regulations was extended by Dr. Gottlieb from August 2018 to 2022. Wednesday’s action chops one year off that extension.

The plan issued on Wednesday is still a draft, and must undergo a 30-day comment period before it can be finalized. It’s an unusual regulatory approach, neither a new rule, nor a voluntary guideline. Instead, the F.D.A. is telling e-cigarette makers that if their products are sold in violation of this request, they can be taken off the market, and forced to apply for agency approval. The F.D.A. can do this under its discretionary enforcement authority.

Dr. Gottlieb is scheduled to have stepped down by that time, and Dr. Norman E. (Ned) Sharpless, director of the National Cancer Institute, was named this week to replace him as acting commissioner.