In a letter addressed to President Luiz Inacio Lula da Silva, Trump criticised the treatment of Bolsonaro as an “international disgrace,” adding that the trial “should not be taking place.”

He also said Washington would launch an investigation into Brazil’s trade practices.

The latest tariff threat came after Brazil said it had summoned the US charge d’affaires in a diplomatic row over Trump’s earlier criticism of the coup trial of Bolsonaro.

Bolsonaro denies he was involved in an attempt to wrest power back from Lula in an alleged coup plot prosecutors say failed only for a lack of military backing.

But Trump previously urged Brazilian authorities to “LEAVE BOLSONARO ALONE” in a social media post.

In unveiling the 50% tariff Wednesday, Trump cited “Brazil’s insidious attacks on Free Elections” among other issues, warning of further escalation if the country retaliated.

While Trump has been issuing letters to trading partners, focusing on those his country runs a deficit with, Brazil had not been among those threatened with higher duties come Aug 1.