TORONTO (AP) — Ontario’s premier, the leader of Canada’s most populous province, announced that effective Monday his province is charging 25% more for electricity to 1.5 million Americans in response to U.S. President Donald Trump’s trade war. Ontario provides electricity to Minnesota, New York and Michigan.

The new surcharge is in addition to the initial round of $30 billion in retaliatory tariffs announced on March 4.

Ontario has placed a surcharge of 25 per cent on electricity exported to the United States as of Monday, and the government says it could raise that amount even higher in response to further American escalation.