The Transport Department on Wednesday reminded motorists that the new HKeToll system will be implemented in the Tsing Sha Control Area on May 7.

From 5am that morning, fee payment for the control area covering the Eagle's Nest, Sha Tin Heights and Tai Wai tunnels will become fully automatic, and drivers will no longer need to stop at toll booths to pay.

Commissioner for Transport Rosanna Law said more than 80 percent of car owners have received their vehicle tags, which are needed to use the system.

For drivers without the tags, they will be issued an automatic demand note to pay the toll within 14 working days.

"They can do so over the HKeToll website or mobile app. They can (pay) through credit card, or they can generate a QR code and go to a convenience store to do so," she said, adding that those who fail to pay on time will have to fork out a surcharge of HK$175.

The three tunnels and their connecting roads will be closed between 2am and 5am on May 7 to facilitate the transition.