EU foreign policy chief Federica Mogherini said Friday that the European Union would protect its interests and pledged proportionate measures to Washington's introduction of tariffs.
She went on stressing that the bloc "is not at war with anyone" on trade, referring to the EU intention to further engage in negotiations on trade issues.
"This doesn't mean the United States are not our closest partners and friends. Allies they [will] stay," she pointed out.
The EU has staged its protest after Washington announced that it was imposing metal tariffs on the European Union member states as well as Canada and Mexico. The bloc immediately responded to the US move, stating that it would proceed with a World Trade Organization (WTO) dispute and impose additional duties on US imports.
However, US Trade Secretary Wilbur Ross assured that the EU's retaliation for the introduction of metal tariffs was unlikely to have much impact on the US economy.
The threat of a full-scale trade war loomed between the transatlantic partners after US President Donald Trump signed a proclamation removing an exemption from metal tariffs of the European Union, Mexico and Canada as of June 1.
The US president's decision to delay imposing higher duties for the EU, Canada and Mexico until June 1 gave the bloc hope for a permanent EU exemption, as the bloc's leaders have repeatedly criticized the tariffs as an act of protectionism by the US administration.