The directive also would require that smokeless electronic cigarettes providing more than a certain amount of nicotine should be available only in outlets like pharmacies. National or Europe-wide “test panels” would determine what quantities of flavoring like menthol should be banned, they said.

Much of the interest in the legislation in recent months had focused on apparent attempts to influence its wording.

Mr. Borg’s predecessor, John Dalli, resigned in October after the commission concluded that he had probably known about an attempt by a lobbyist to solicit a multimillion-dollar payoff in exchange for easing the ban on snus. The product can be sold only in Sweden, where some people consider it a safer alternative to smoking.

Mr. Dalli denied the allegations and said he was forced to resign under pressure from José Manuel Barroso, the president of the commission. Mr. Dalli also said his ouster had jeopardized chances for the revised directive to be passed before the current term of the European Parliament, which must approve the legislation, expires in 2014.

Mr. Borg suggested Wednesday that the law still could be adopted before the Parliament’s term expires, and go into force in 2015 or 2016.

But the Smoke Free Partnership warned that lobbying still could water down the proposals on labeling and packaging, as well as the ban on flavors and slim cigarettes. Governments and members of the European Parliament “are likely to face attempts by the tobacco industry to further block, weaken and delay this important legislation,” said Florence Berteletti Kemp, the director of the partnership.