Canada is drawing up plans for extensive tariffs against US products if Donald Trump follows through on his threat to put 25% levies on Canadian goods, according to people familiar with the matter.

Trump has threatened a tariff on goods from Canada if the country does not clamp down on immigration and the flow of drugs across its border with the U.S.

Donald Trump said this week he will use economic coercion to pressure Canada to become the nation’s 51st state.