The European Union's retaliatory tariffs on a list of products in response to the United States tariffs on steel and aluminium will come into effect on Friday, the European Commission announced on Wednesday.

The list of U.S. imports worth 2.8 billion euros (3.24 billion U.S. dollars), which will now face an extra duty at the EU border, includes steel and aluminium products, agricultural goods and a combination of various other products.

The remaining U.S. products valued at 3.6 billion euros will take place at a later stage, either in three years' time or after a positive finding in WTO dispute settlement if that should come sooner.

"We did not want to be in this position. However, the unilateral and unjustified decision of the U.S. to impose steel and aluminium tariffs on the EU means that we are left with no other choice," said EU

Trade Commissioner Cecilia Malmstrom.

The U.S. has applied 25 percent tariffs on the EU steel products and 10 percent tariffs on aluminium from June 1.