The European Commission called for industry views on Friday on a list of U.S. products it will subject to import tariffs if the United States taxes European steel and aluminum.
The Commission plans to set duties of 25 percent on a range of U.S. products, from maize to motorbikes, whose annual imports to the European Union are worth some 2.8 billion euros ($3.45 billion).
U.S. President Donald Trump signed an order last week that would subject incoming steel to a tariff of 25 percent and aluminum 10 percent, albeit with exemptions for Canada, Mexico and possibly other countries.
The European Commission, which oversees trade policy for the 28-member European Union, is still unclear how it might secure an exemption. U.S. Commerce Secretary Wilbur Ross and EU Trade Commissioner Cecilia Malmstrom are due to discuss the issue at a meeting next week.
EU officials warn that without an exemption they will notify the World Trade Organization (WTO) of potential counter-measures by May 23, or within 60 days of U.S. tariffs coming into force.
The ten-page list of products the EU may subject to tariffs ranges from different types of grains, food exports like fruit juices to clothing, household appliances and boats. It also includes many metals products for use in construction and industry.
Some of the products would be subject to duties within months. Another group would only incur duties if the WTO later declared the U.S. tariffs illegal or after a period of three years.
The two combined would be aimed to counter-balance the estimated 6.4 billion euros of damage U.S. measures would inflict on the bloc's aluminum and steel sectors.
The Commission has asked "private stakeholders" affected by the U.S. tariffs and the EU's possible response by March 26.
($1 = 0.8114 euros)
Reporting by Philip Blenkinsop.