The European Union warned there will be retaliation for any restrictions placed on steel imports to the US.

The Times of London reports that Brussels is preparing a response to possible restrictions implemented by the Trump administration, pending a review of the national security implications of steel production.

“If the worst comes to the worst and there’s a general inclusion of steel tariffs under those 232 provisions, that would be very bad for Europe,” said Cecilia Malmstrom, the European trade commissioner. “We’re a friend and an ally of the US and would be unjustifiably hit by this.”

“We will have to see if this measure is in compliance with the World Trade Organisation and if it hits us like it could, we will, of course, retaliate. Exactly how and when I will not say, but we’re making preparations.”