WASHINGTON — President Donald Trump said he will announce on Monday that the United States will impose 25% tariffs on all steel and aluminum imports, including from Canada and Mexico, as well as other import duties later in the week.

“Any steel coming into the United States is going to have a 25% tariff,” he told reporters Sunday on Air Force One as he flew from Florida to New Orleans to attend the Super Bowl. When asked about aluminum, he responded, “aluminum, too” will be subject to the trade penalties.

Trump also reaffirmed that he would announce “reciprocal tariffs” – “probably Tuesday or Wednesday” – meaning that the U.S. would impose import duties on products in cases where another country has levied duties on U.S. goods.

“If they are charging us 130% and we’re charging them nothing, it’s not going to stay that way,” he told reporters.

Trump’s comments are the latest example of his willingness to threaten, and in some cases to impose, import taxes. Tariffs are coming much earlier in his presidency than during his previous four years in the White House, when he prioritized tax cuts and deregulation. Trump has alternately said he sees import taxes as tools to force concessions on issues such as immigration, but also as a source of revenue to help close the government’s budget deficit.

Financial markets fell on Friday after Trump first said he would impose the reciprocal tariffs. Stock prices also dropped after a measure of consumer sentiment declined on Friday, largely because many respondents cited tariffs as a growing worry. The survey also found that Americans are expecting inflation to tick up in the coming months because of the duties.

Trump on Sunday did not offer any details about the steel and aluminum duties, or the reciprocal tariffs. Trump previously threatened 25% import taxes on all goods from Canada and Mexico, though he paused them for 30 days barely a week ago. At the same time, he proceeded to add 10% duties on imports from China.

Yet on Friday, he said he would also delay the tariffs on the millions of small packages – often from fast-fashion firms such as Temu and Shein – until customs officials can figure out ways to impose them. The small packages have previously been exempt from tariffs.

Trump’s latest remarks stirred immediate worry from some global trading partners.

South Korea’s acting president, Choi Sang-mok, called a meeting with the country’s top foreign policy and trade officials on Monday to examine how Trump’s proposed tariffs on steel and aluminum would affect its industries.

The office of Choi, who also serves as the country’s finance minister, said officials discussed the potential impact and Seoul’s possible responses, but specific details of the meeting were not disclosed. The stock prices of major South Korean steelmakers, including POSCO and Hyundai Steel, dropped as the market opened on Monday. South Korea shipped about $4.8 billion worth of steel to the United States from January to November last year, which accounted for 14% of its global exports of the products during the period.