Donald Trump pledged on Saturday to make it too costly for countries to shift away from using the US dollar, adding a new pillar to his tariff platform. 

“You leave the dollar and you’re not doing business with the United States because we are going to put a 100% tariff on your goods,” the Republican presidential nominee said at a rally in the battleground state of Wisconsin. 

The statement follows months of discussions between Trump and his economic advisers on ways to penalize allies or adversaries who seek active ways to engage in bilateral trade in currencies other than the dollar. 

Options have included export controls, currency manipulation charges and tariffs, people familiar with the matter have previously told Bloomberg News. 

Trump, who has long embraced protectionist trade policies, said the dollar has been “under major siege” for eight years. China, India, Brazil, Russia and South Africa discussed de-dollarization at a summit last year. By contrast, Trump has said he wants the dollar to remain the world’s reserve currency, a pledge he renewed at Saturday’s rally.

While dollar dominance has lessened in recent decades, the US currency still accounted for 59% of official foreign exchange reserves in the first quarter of 2024, with the euro second at almost 20%, according to the International Monetary Fund.

Wisconsin is among the most critical swing states in the race between Trump and Democratic rival Kamala Harris. The two are fighting for the support of the state’s working-class voters, who are uneasy with President Joe Biden’s economic agenda and drawn to Trump’s populist appeals.

A Bloomberg News/Morning Consult poll released last week showed Harris leading in Wisconsin by 8 percentage points, the largest lead over Trump she has among the seven battleground states in the poll.

Trump’s Wisconsin rally caps off a campaign swing that included Pennsylvania and North Carolina, as well as a stop in his hometown of New York City where he delivered an economy-focused address and held a press conference.

Harris spent Saturday in Pennsylvania preparing for a Tuesday debate with Trump, the next big test that could change the course of the close race.

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