Secretary of Commerce Wilbur Ross said Thursday that the Trump administration has initiated a sweeping investigation of how trade has affected national security and the U.S. economy.

"Last night the Department of Commerce initiated an investigation under section 232 of the Trade Expansion Act of 1962," Ross told reporters at the White House on Thursday. "That authorizes the secretary of commerce to conduct comprehensive investigations to determine the effects of imports of any particular item into the United States on the security of the country."

Ross highlighted the problem rampant foreign steel imports have created for U.S. manufacturers, noting the investigation would look in part at whether the domestic industry currently has the ability to meet the needs of the military as it prepares to ramp up production of tanks, aircraft and naval ships.

"No decision has been made to take any concrete actions as yet," Ross said.

The investigation comes as Trump administration officials weigh changes to U.S. trade relationships, including with China.

One aspect of the investigation would examine the "incremental effects" of additional tariffs on steel imports, including whether tariffs would cause a burdensome spike in the price of U.S. steel.

Under the Trade Expansion Act, the administration must complete the investigation within 270 days.

"We think it'll be accomplished a lot sooner than that," Ross said, adding that the Commerce Department anticipated holding "at least one" public hearing.

President Trump has long promised to renegotiate trade deals and implement measures to protect U.S. industries. Officials have said they will base their trade-related decisions on the results of the review.

Trump signed a memorandum authorizing the trade investigation later Thursday.

"We're going to fight for American workers and American-made steel," Trump said.

The president noted he has long fought to reverse "unfair foreign trade," and vowed to do more to protect U.S. industries using the results of the investigation.

"Other countries have made a living taking advantage of the United States," Trump said.

He said the trade investigation would help the administration tackle practices, such as "steel dumping," that harm American manufacturing.

Trump repeated his assertion that NAFTA, which he has promised to renegotiate, is a "disaster" for the U.S. economy.