BRUSSELS — The European Union’s top trade official said Friday that the 28-nation bloc will seek to be excluded from President Trump’s steel and aluminum tariffs, a day after he signed off on them with the caveat that countries with a “security relationship” could seek an exemption.

E.U. Trade Commissioner Cecilia Malmstrom said that Europe shared American concerns about China’s support for its steel industry, but she said that the tariffs of 25 percent on steel and 10 percent on aluminum were the wrong way to address the issue.

“We share the concern of overcapacity in the steel sector,” Malmstrom told a conference in Brussels. “This is not the right way to deal with it.”

She said that E.U. officials were still trying to understand Trump’s announcement Thursday, in which he slammed countries around the world for unfair trade practices but left open the door to trade partners to seek exemptions. Canada, which is the top source for U.S. steel imports, and Mexico are both excluded from the tariffs. 

Here's how leaders around the world are reacting to President Trump's proposed tariffs on steel and aluminum. (Sarah Parnass/The Washington Post)

Trump said these exemptions were to facilitate negotiations for a revised North American Free Trade Agreement (NAFTA). 

Trump has cited national security concerns as the legal basis for the tariffs. European policymakers have dismissed that as nonsensical, because most U.S. steel imports come from its military allies.

“We are friends, we are allies, we work together. We cannot possibly be a threat to national security in the U.S.,” Malmstrom said. 

“We count on being excluded,” she said, adding that the policy announced by Trump was “not crystal clear.”

Malmstrom will meet Saturday in Brussels with U.S. Trade Representative Robert E. Lighthizer and Japanese Trade Minister Hiroshige Seko for a meeting that was originally scheduled to discuss cooperation about Chinese trade issues but has now transformed into something more adversarial.

In the meeting, E.U. officials said they will ask how to apply for an exemption.

“This is not a trade negotiation, now we are talking about unilateral actions against international rules. And we want to sort it out before it becomes a problem,” said Jyrki Katainen, a top E.U. economic official. “We want to get as much as clarity as possible tomorrow. Most probably discussions will continue.” 

But Europeans are preparing actions if they are ultimately hit with tariffs.

E.U. policymakers have readied about $3.5 billion in countermeasures that will strike against symbolically important products from the United States — such as bourbon, motorcycles and blue jeans — that are manufactured in the home districts of congressional leaders. They also plan to file a complaint with the World Trade Organization.

The back-and-forth risks a broader trade war of escalating tariffs, but many European leaders think that if they do not respond, they will soon be hit again by the White House.

German Chancellor Angela Merkel, leader of Europe’s largest economy, offered her support for the E.U. measures being readied, although she said she would prefer a broader dialogue about lowering tariffs and reaching a trade agreement with Washington. 

She told reporters Friday that she hoped to avoid a damaging trade fight with Washington.

“No one would win such a competition,” she said.

Quentin Ariès contributed to this report.