As president Donald Trump's tariff regime on goods entering the United States from 69 countries around the world comes into effect, we discuss the impact it will have on global trade. With India facing a threat of 50% tariffs on exports to the US due Delhi's purchase of oil from Russia, we hear whether India will ever wean itself off Russian supplies? And what will be the impact of Washington's tariff mark-ups on Brazil and Switzerland? Elsewhere, with the world's most revered investor - Warren Buffett - set to step down, Roger Hearing finds out who the 'sage of Omaha' really is. The latest business and finance news from around the world, on the BBC.