The government on Wednesday approved allowing autonomous vehicles in Tung Chung, as part of a trial scheme that began half a year ago.

A subsidiary of mainland tech giant Baidu, Apollo Go, has been running 10 cars around the airport, and the Transport Department said the trial has made significant progress so far.

"The department has expedited ongoing monitoring, proactively taken forward the project and granted approval under the new autonomous vehicles regulatory framework," it said in a statement.

"We achieved several technical advancements within months."

Officials said the progress so far includes the use of roads with more complex traffic scenarios and allowing all 10 autonomous vehicles to hit the road at the same time in order to collect more data.

The maximum speed for the trial was also raised to 50 kilometres per hour.

Now that the scheme is being expanded to the heart of Tung Chung, officials say three private cars at most are allowed to take part in each road test.

Officials stressed that there are signs on the autonomous vehicles so people can identify them.

They added that they welcome organisations or companies to submit similar pilot licence applications for operating automated cars.