Prime Minister Theresa May hinted at a trade war with the U.S. after the U.S. Department of Commerce decided Canadian aircraft company Bombardier, which constructs its planes in the U.K., "should be subject to 219 per cent import duty," the Telegraph reports.

Why now: This comes after Boeing "complained that Bombardier had been given unfair state aid," and May said the American company's partnership with the U.K.'s government was being "undermined" by its behavior. The U.S. International Trade Commission is expected vote next year to finalize the tariffs. Per the Telegraph, the dispute cast doubt "on a key plank of [May's] Brexit strategy."