Advance bookings for summer flights between Canada and the U.S. have dropped by 70% as tensions rise between the two governments.

Airline travel between the U.S. and Canada has dropped by 70% compared to the same time last year, the result of dueling tariffs between the two countries and U.S. overtures to make Canada the 51st state.

Statistics Canada writes that the number of Canadians returning to the United States by car went down 23 percent in February. The data also showed that Canadian residents flew back from 585,700 trips to the United States in the same month, a 13.1 percent decline from last year.