U.S. Commerce Secretary Wilbur Ross said on Tuesday the Trump administration has not ruled out imposing tariffs on imported autos, after letting a review period end in November with no action.

“We’ve been having negotiations with the individual companies. We’ve had some very good benefits from that,” Ross told Reuters in New York. “It may or may not turn out that there is any need for the tariff.”

U.S. President Donald Trump did not announce any new tariffs after a six-month, self-imposed review period expired in mid-November following a Commerce Department investigation into whether imported autos pose a national security threat. He has threatened to tax them by as much as 25%.

Asked if there was a new deadline, Ross referred to a White House statement last month that did not include a new deadline.

Auto experts have said the U.S. administration may have to find other means if Trump wants to tax European or Japanese car imports, a key part of Trump’s pledge to make America’s trade relationships more fair.