The United States today announced an additional 25% tariff on all Indian imports, on top of an existing 25% duty, taking the total to 50% from August 27. The White House said the measure responds to India’s continued purchase of Russian oil.The move places India among the most heavily taxed US trading partners, far above rivals such as China, Vietnam, and Bangladesh, and threatens most of India’s $86.5 billion in annual exports to the US, from textiles to machinery.