Transport Commissioner Rosanna Law on Friday said that the coming Monday will be a real test for the e-toll system, as the system will be launched at one of the busiest tunnels in the city.

Speaking on a Commercial Radio programme, Law said drivers using the Lion Rock Tunnel would no longer need to stop at booths to pay tolls starting from 5 am on Sunday.

Law said the first stage of road closures will begin on Saturday at 10 pm for officers to close down toll booths and change traffic signs, and the tunnel will be entirely closed from 4:30 am to 5 am.

The closure will affect more than ten overnight bus and minibus routes, the transport commissioner said.

Law said most drivers are now aware of the arrangements due to extensive media coverage, and that the system is currently handling more than 110,000 vehicles a day.

But she said the true test for the high-traffic tunnel will come on Monday morning when people head to work and school.

"Will there be no traffic jams after the implementation of the e-toll? It may not have a significant impact, but once everyone gets familiar with [the new system], there won't be a bottleneck at the toll plaza at the tunnel, which will make the journey even smoother," Law said.

She said the traffic situation is expected to improve after the implementation of the three-tunnel toll system at the end of the year, in which different tolls will be charged at different times.