U.S. officials are abandoning plans to require sleep apnea screening for train engineers and truck drivers in the latest step of President Donald Trump's campaign to drastically slash federal regulations.

Safety experts say millions of lives are at risk if commercial drivers are behind the wheel with an undiagnosed disorder that causes daytime drowsiness.

The Federal Railroad Administration and Federal Motor Carrier Safety Administration said Friday that they are no longer pursuing the regulation that would require testing for the fatigue-inducing disorder.

Sleep apnea has been blamed for deadly rail crashes in New York City and New Jersey and several highway crashes.

Federal regulators say current safety programs are sufficient and companies can choose to screen their employees.

The National Transportation Safety Board says it's disappointed by the decision.