BRUSSELS—The European Union has experienced a “breakthrough year” with the United States even if not all trade irritants are gone and now wants to work with its transatlantic ally to start forging trade rules for the future, the EU trade chief said. “One can say that this year was indeed a breakthrough year for EU–U.S. trade relations,” European Commission Executive Vice-President Valdis Dombrovskis said in an interview for the Reuters Next conference. On steel, the United States has replaced tariffs on all EU imports with tariff-free quotas based on historical volumes. Dombrovskis said the end result in two years had to be a complete lifting of tariffs and quotas. Brussels was also looking closely at the United States’ “Buy American” agenda aimed at ensuring that federal agencies buy American-produced goods as much as possible. Dombrovskis said the EU would look at the extent to which Washington respects its international commitments. …