President Donald Trump spoke with members of Congress on Tuesday about possible tariffs on steel and aluminum.

Trump said he was concerned that foreign countries like China were dumping cheap steel and aluminum on the United States, hurting the country’s steel industry.

“It’s a sad thing to look at,” Trump said, pointing to diminished steel companies and abandoned steel factories across the country.

Trump met with several senators to discuss the issue at the White House on Tuesday, including Democrats Sherrod Brown, Bob Casey, and Ron Wyden.

During the meeting, Missouri Sen. Roy Blunt warned Trump that an increase in tariffs could spark a sharp jump in steel prices.

“We need to be careful here that we don’t start a reciprocal battle on tariffs,” he said. “We make aluminum, and we make steel in Missouri, but we buy a lot of aluminum, and we buy a lot of steel as well.”

Trump acknowledged that cheap prices for steel were important, but not at the expense of American industries.

“I look at it two ways,” he said. “I want to keep prices down, but I also want to make sure that we have a steel industry and an aluminum industry, and we do need that for national defense.”

Trump said he was concerned about keeping the steel industry alive for national security.

“If we ever have a conflict, we don’t want to be buying steel for a country we are fighting,” he said.