President Donald Trump's order imposing new tariffs on scores of countries and the European Union starting in seven days has injected a new dose of uncertainty in an already uncertain process.

U.S. President Donald Trump on Wednesday imposed a 25% tariff on goods imported from India starting August 1, as well as an unspecified penalty for buying Russian arms and oil - moves that could strain relations with the world's most populous democracy.

US President Donald Trump said he would impose a tariff of at least 25% on India's exports to the US starting Friday, though later added that the two sides were still in talks.