(Reuters) - The U.S. National Highway Traffic Safety Administration (NHTAS) said Wednesday it is reviving a long-stalled effort to overhaul the five-star crash rating program for all new vehicles.

FILE PHOTO: Traffic travels along a highway next to Los Angeles, California, U.S. October 11, 2019. REUTERS/Mike Blake

In 2015, under President Barack Obama, NHTSA proposed requiring automakers to add crash avoidance technologies to gain top, five-star ratings as part of its New Car Assessment Program (NCAP). Those changes were set to start in the 2019 model year but have been on hold as the auto safety agency held additional public hearings.

NHTSA’s acting chief, James Owens, said in a statement Wednesday the agency would propose “propose significant updates and upgrades” in 2020 “by creating additional market-based incentives for automakers to continue investing in innovative safety technologies that will save lives and prevent injuries.”

On Thursday, a group plans to hold a press conference in Washington criticizing NHTSA’s failure to update the ratings. The National Transportation Safety Board has recommended pedestrian collision avoidance systems and forward collision avoidance systems to be added to the program.

Critics note the vast majority of new vehicles achieve four or five-star ratings, making it difficult for consumers to differentiate between vehicles.

NHTSA said potential changes include “new test procedures, updates to vehicle labeling, advancements in crash-test dummies... and new technologies tied to the safety of pedestrians and other vulnerable road users such as cyclists.”

The 2015 proposal sought to prod automakers to add advanced technologies including forward collision warning, lane departure warning, blind-spot detection, lower beam head lighting, semi-automatic headlamp beam switching, amber rear turn signals, rear automatic braking and pedestrian automatic emergency braking and to factor those in to setting the ratings of up to five stars.

The Alliance of Automobile Manufacturers, a trade group representing General Motors Co GM.N, Volkswagen AG VOWG_p.DE, Toyota Motor Corp 7203.T and others, told NHTSA last year "it is important that any new additions to NCAP significantly increase real-world safety. If not, they will

only increase vehicle cost without any commensurate real-world safety benefit.”

Automakers covet five-star ratings, so new rules could effectively require manufacturers to make technology currently offered as pricey options on some vehicles standard equipment on all vehicles.

NHTSA in 2015 proposed adding a new frontal crash test, new pedestrian crashworthiness testing and add two new advanced crash test dummies.

The tests are only to set crash ratings included on new car window stickers - not for crash tests needed for U.S. vehicles to be legally sold.