Washington (CNN) President Donald Trump on Wednesday accused Japan of using a "bowling ball test" to cheat US auto companies out of selling cars to Japanese consumers. A White House spokeswoman said Thursday he was joking.

"It's the bowling ball test. They take a bowling ball from 20 feet up in the air and drop it on the hood of the car," Trump said of Japan during a fundraising speech in Missouri, according to audio obtained by The Washington Post and confirmed to CNN by an attendee.

"If the hood dents, the car doesn't qualify. It's horrible," Trump told the donors.

Trump did not go into further details. But Japan and other international markets do have higher safety standards for automobiles, particularly to protect pedestrians' heads when they are struck by vehicles, Grant Faulkner, vice president of auto industry consultants LMC Automotive, told CNN.

White House press secretary Sarah Sanders, asked about the comment on Thursday, said Trump was "obviously ... joking."

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