Commissioner for Transport Rosanna Law on Friday said officials have received e-toll vehicle tag applications for over 85 percent of the city's cars.

She made the comment as she renewed her call for motorists to get ready for the new HKeToll system, which launches on May 7 at the Eagle's Nest, Sha Tin Heights and Tai Wai tunnels.

"If you haven't opened an account or linked it to an auto-payment method, please do so in the next two days," said Law.

"Remember to affix the vehicle tag onto your vehicle before 5am on May 7, so you can use tunnels more easily."

Drivers who don't have a tag will instead be sent a bill for their tunnel use.

Officials earlier said they aimed to extend the e-toll system to all government tunnels later this year.