Forty countries led by Japan and the European Union (EU) but not the United States or China have agreed to require new cars and light commercial vehicles to be equipped with automated braking systems starting as soon as next year, a United Nations agency said on Tuesday.

The regulation will require all vehicles sold to come equipped with the technology by which sensors monitor how close a pedestrian or object might be. The system can trigger the brakes automatically if a collision is deemed imminent and if the driver doesn't appear set to respond in time.

The measure will apply to vehicles at “low speeds" — 60 kilometres per hour (42 mph) or less, and only affects new cars sold in the markets of signatory countries so vehicle owners won't be required to retrofit their cars and trucks already on the roads today.

The US, China and India are members of the UN forum that adopted the new regulations. However, they did not take part in the negotiations because they want to ensure that their national regulations keep precedence over the UN rules when it comes to the auto industry.

In 2016, 20 automakers reached an agreement with the US government to put automatic emergency braking on all new vehicles by September of 2022, but compliance is voluntary. In the most recent report on the safety technology from 2017, the National Highway Traffic Safety Administration said that four of the 20 automakers Tesla, Mercedes-Benz, Toyota and Volvo had made automatic braking standard on more than half their models.

Data from the insurance industry's Highway Loss Data Institute show that 28 per cent of 2019 US models have standard automatic emergency braking. Another 36pc have it as an option.

Jason Levine, executive director of the nonprofit Center for Auto Safety, said lack of the US participation in the UN group is embarrassing for a country that once led in the auto safety sector.

“It is yet another indication of the auto industry in the US and the Trump administration's complete lack of leadership when it comes to the safety of everyone on the road,” Levine said on Tuesday.

A message was left on Tuesday seeking comment from NHTSA, the US highway safety agency. The requirement will start taking effect next year first in Japan, where 4 million cars and light commercial vehicles were sold in 2018, said Jean Rodriguez, the spokesman for the agency, called United Nations Economic Commission for Europe (UNECE).

The European Union, and some of its closest neighbors, is expected to follow suit in 2022.

The UNECE says the countries that agreed to the deal want to be more pro-active in fighting roadway accidents, particularly in urban settings where obstacles like pedestrians, scooters, bicycles and other cars in close proximity abound.

The agency pointed to more than 9,500 roadway deaths in the EU in 2016, and the EU Commission estimates that the braking systems could help save over 1,000 lives a year in the bloc.

Apparently wary that the regulations might be seen as a step toward giving artificial intelligence precedence over humans, the drafters put in clear language in their resolution: A driver can take control and override these automated braking systems at any time, such as through “a steering action or an accelerator kick-down”.

The UNECE says the new rules build on existing UN rules on the braking system for trucks and buses, mainly for safety in higher-speed motorway conditions.