New Canadian Prime Minister Mark Carney and his Conservative opponent said U.S. President Donald Trump must respect Canada’s sovereignty as they kicked off their election campaigns Sunday against the backdrop of a trade war and annexation threats from Trump.

Canadian Prime Minister Mark Carney called Sunday for a snap election to be held in April, in which Canadian voters will elect either him or his rival in the Conservative Party, saying he wants a strong mandate as the country faces a “significant threat” from President Donald Trump and his administration’s tariff war with Canada.