TOKYO -- Japan's push to become Asia's leader in self-driving cars got a boost Thursday, when the authorities unofficially approved the testing of driverless cars on public roads.

The rules, released the same day by the National Police Agency, will officially take effect by the end of May, pending feedback from the public.

It is the first time the agency has greenlighted the use of driverless vehicles on public roads. Once the rules are made official, companies and research institutes will be able to test their cars in real traffic situations, which would likely speed up their development work and help them amass knowledge more quickly.

A company must meet three conditions to receive a test permit from the NPA: The technology must have already been tested on a track; the test vehicle must be equipped with a telecommunications system; and the driving conditions during testing must be monitored remotely with the same degree of precision as a person sitting in the driver's seat.

The NPA also said prospective applicants should first seek to win the consent of residents living around the planned testing site. The agency could begin accepting applications as early as summer.

Should the tests lead to practical applications for the cars, it could help ease Japan's shortage of drivers for transport services and offer an alternative means of transportation in depopulated areas.

Get on the bus

Neighboring South Korea, which also has big ambitions for the technology, already allows testing of driverless cars on public roads -- though at least two passengers must be in the car. The government offers permits for entities looking to test driverless cars in real-world conditions. So far, permits have been granted for 12 vehicles from seven institutions, including Hyundai Motor, Kia Motors and Seoul National University. They are allowed to test their vehicles anywhere except for in areas designated as requiring special protection for children, the disabled and the elderly.

According to a report published in January by the country's Ministry of Land, Infrastructure and Transport, the government plans to introduce a self-driving bus on a route between Seoul's Pangyo subway station and Pangyo Techno Valley in December. This would make South Korea one of the first countries to put autonomous vehicles to actual use.

The ministry also said that before the bus makes its debut, it will revise the legislation requiring testers to be on board self-driving vehicles, according to the local Yonhap News Agency.

Singapore dreams

Also keen to put driverless autos on the roads is Singapore.

Working with industry partners, the government has been conducting tests on public roads in selected areas since 2015. In February this year, the parliament passed amendments to the Road Traffic Act to introduce a suite of rules for testing on public roads.

The law sets out design and construction rules for autonomous vehicles, including a requirement to equip them with functions that capture and store sensor data and video footage from the vehicle. Also mandatory will be an alert system that notifies an individual to take immediate action in the case of an emergency. Developers will be required to share with the government information they gather through testing, including sensor data and video footage.

The rules will be in force for five years, after which the government will decide whether to extend or make them permanent.

Murky area

China has an ambitious roadmap for driverless cars, but the testing of vehicles on public roads remains largely a murky area.

Last April, Chongqing Changan Automobile had its self-driving car complete a 2,000km road trip from its headquarters in southwestern China to Beijing in six days. But the country's regulators later warned that automakers should not conduct highway testing before regulations are officially rolled out.

A preliminary draft of the rules is underway, according to media reports, and is expected to include technical standards for driverless cars across China, a deviation from the more fragmented regulations, which vary state by state in the U.S.

Industry observers attribute the slow progress of legislation to bureaucracy. "In all, nearly 10 ministries and departments have jurisdiction over some aspect of autonomous vehicles," said Darrell West, founding director of the center of technology innovation at U.S.-based think tank the Brookings Institution, in a report published last fall. "Getting these agencies to coordinate and work together is the task of current planners."

Still, China aims to have half of its cars sold to have some forms of autonomy by 2020 and 10% of cars to be fully autonomous by 2030, according to a blueprint by the Ministry of Industry and Information Technology and an industry body.

The government set up last June its first enclosed national test base in Shanghai, where driverless vehicles from SAIC Motor and Volvo underwent pilot testing, and is looking to expand its test programs.

Nikkei staff writers Kim Jaewon in Seoul, Tomomi Kikuchi in Singapore and Jennifer Lo in Hong Kong contributed to this report.