A new Honolulu City Council bill would ban people under 21 years old from purchasing tobacco and electronic smoking products on Oahu.

Bill 51, introduced by Councilman Stanley Chang and Council Chairman Ernie Martin Thursday, would take effect Jan. 1, 2015 if approved. Those 18 or older on or before Dec. 31 would be "grandfathered," or exempted, from the ban.

Federal law prohibits purchase of such products by anyone under 18. A Hawaii County under-21 ban on tobacco and electronic smoking products became law July 1.

Chang, in a press release, said tobacco use costs more than $330 million in health care costs annually in Hawaii and is responsible for 1,200 residents each year.

"By increasing the smoking age, we are aiming to try and prevent the number of young, regular daily smokers and prevent the number of early deaths," Chang said.