In a bid to crack down on secondhand smoke ahead of the 2020 Tokyo Olympics amid a global trend toward a cleaner environment, Japan is set to ban smoking in more places and impose penalties on offenders for the first time.

Under a draft proposal the Health, Labor and Welfare Ministry compiled Wednesday, smoking will be completely banned indoors at public facilities such as stadiums, government offices and welfare institutions. At schools and medical facilities where minors and patients visit, smoking will be banned both indoors and outdoors.

As for places such as restaurants, offices and hotels, where people often inhale secondhand smoke, the proposal is somewhat ambiguous, stating that smoking will be prohibited "in principle."