The U.S. and the European Union have been at odds over subsidies to the world's top two plane makers - Boeing and Europe's Airbus. A WTO panel has also ruled that European governments provided $18 billion in subsidies to Airbus, though not all were deemed illegal.
The trade office claimed the U.S. had complied with the March WTO ruling by stopping select payouts to Boeing through NASA and the Pentagon, and by removing some beneficial tax and funding policies. It did not specify a cost of the measures.
The EU said Monday it will review the U.S. compliance measures.