Ban on sale of e-cigarettes to minors has been a move by the most populous province of Canada on Monday, to regulate their use the same way as tobacco.
Associate Health Minister Dipika Damerla unveiled the legislation at a nationally-televised press conference.
The new rules starting on January 1, 2016, will effectively ban e-cigarettes wherever smoking is already prohibited -- largely in public places.
Anyone breaking the law will face fines.
E-cigarettes do not contain tobacco and produce an aerosol instead of smoke.
Proponents say they are useful in helping smokers quit their habit, but public health advocates are concerned that they also carry a risk of addiction with uncertain risks.
"If young kids see people smoking or vaping, they're more likely to take up smoking or vaping," said Damerla.
Ontario is also banning all flavored tobacco products, including menthol cigarettes, which the government says are designed to appeal to teens.