The United States has revoked the visa of Brazil’s ambassador, a State Department official said Tuesday, deepening a diplomatic dispute months before elections in Latin America’s largest nation. The official, speaking on condition of anonymity, said the move would be reversed if Brazil approves President Donald Trump’s nominee to be ambassador to Brasilia. Trump nominated Daniel Perez, a prominent Florida Republican, to the post in early June. The revocation marks a sharp escalation in tensions between the two countries, coming just ahead of Brazil’s presidential elections. Neither report indicated how the ambassador learned of the action or how Brazil’s government has responded so far.