President Donald Trump signed executive orders on Monday to impose universal 25 percent tariffs on all aluminum and steel supplies entering the U.S., regardless of the country of origin.

Foreign aluminum and steel imports, including from Canada and Mexico, are subject to the tariffs. The action marks a change from Trump’s 2018 aluminum and steel tariffs, which had exemptions for Canada and Mexico at the time.

“President Trump’s bold actions restore the strength of America’s steel and aluminum industries and puts an end to the rampant exploitation and circumvention that has hurt American workers,” a senior White House official told reporters as Trump signed the tariff orders in the Oval Office. “With these tariffs, the days of foreign nations gaming our trade system are over.”

The order was expected after Trump said he would place a hefty tariff on aluminum and steel imports. The president is expected to announce reciprocal tariffs in the coming days, targeting countries that have levied tariffs on U.S. goods.

“If they are charging us 130 percent and we’re charging them nothing, it’s not going to stay that way,” he told reporters aboard Air Force One on Sunday.

Trump previously placed 25 percent tariffs on products coming from Canada and Mexico before the taxes were ultimately paused amid negotiations with the U.S. Both neighboring nations agreed to help the White House curb illegal immigration and fentanyl trafficking.

Mexican President Claudia Sheinbaum and Canadian Prime Minister Justin Trudeau each agreed to send 10,000 troops to the southern and northern borders, respectively, among other measures.

Trump also placed a new 10 percent tariff on China last week in an effort to compel the nation to stop the flow of fentanyl precursor chemicals. China is the primary source of the synthetic opioid materials. That tariff still remains in effect.

China hit back with retaliatory tariffs of its own, specifically targeting U.S. coal and liquefied natural gas in addition to farm equipment and other products. Those took effect on Monday.

The tit-for-tat tariffs have ignited concerns about a global trade war between the U.S. and China, the world’s two largest economies, which could raise prices for American consumers and businesses. Trump began setting tariffs on China during his first term to punish the nation for engaging in unfair trade practices.

The new tariffs on aluminum and steel are similar to ones that Trump enacted in 2018 to secure America’s economic and national security interests. During Trump’s first term, however, Canada and Mexico were excluded from those tariffs.

Trump’s trade and manufacturing adviser Peter Navarro said the newly signed tariffs would protect American steel and aluminum producers.

“The steel and aluminum tariffs 2.0 will put an end to foreign dumping, boost domestic production, and secure our steel and aluminum industries as the backbone and pillar industries of America’s economic and national security,” Navarro said.

“This isn’t just about trade. It’s about ensuring that America never has to rely on foreign nations for critical industries like steel and aluminum.”