The Seoul municipal government on Sunday said it plans to expand no-smoking zones at subway entrances to better address public health concerns.

Under the changes that will go into effect as of Sept. 1, people caught smoking within 10 meters of a subway entrance can be fined up to 100,000 won ($89.6).

It said a campaign has been launched in cooperation with the capital city's many wards to raise public awareness for the shift.

"Stickers and notices have been placed where needed to warn smokers of the changes and the penalties involved for violators," a city official said.

Seoul plans to conduct an intense campaign throughout August to get citizens to voluntarily avoid smoking near subway entrances.

Seoul and South Korea as a whole have stepped up efforts to discourage smoking in public areas. (Yonhap)