Nine out of 12 graphic warnings on cigarette packs will change starting Wednesday, as part of efforts to show the harmful effects of smoking more clearly, health authorities said Monday.

Products with new warnings will be sold at retail stores from the end of January next year.

The new graphic warnings include more alarming images of the harmful effects of smoking in lung cancer, oral cancer, heart disease and stroke.

The current images of laryngeal cancer and sexual dysfunction, as well as the picture on heated tobacco products, will not be replaced, as they were thought to be highly effective, officials said.

The move comes to boost effectiveness of the warning against smoking and tobacco use by replacing the existing warning pictures that had been used for too long, according to the Ministry of Health and Welfare.

Under the Enforcement Decree of the National Health Promotion Act, the warning images and messages on cigarette packs should change every two years. The current images had been displayed on the tobacco packs since Dec. 23, 2018.

In addition to changing the warning pictures on a regular basis, the ministry plans to introduce standard packaging regulations that restrict the color and design of cigarette packaging to curb their advertisement effects.

The tobacco sales and smoking rate among adult males have steadily decreased since the installation of warning pictures and phrases on cigarette packs in 2016.

By Kan Hyeong-woo (hwkan@heraldcorp.com)