The US economy will feel the pain if Trump goes ahead with his plan to whack countries buying Moscow’s oil with fresh tariffs on their goods.

"The key channel by which secondary tariffs on buyers of Russian energy could impact the global economy would be through the level of energy prices," says Kieran Tompkins from the consultancy Capital Economics. If the tariffs work, they will cut the flow of Russian oil and gas to global markets.

U.S. President Donald Trump again threatened on Monday to raise tariffs on goods from India over its Russian oil purchases, while New Delhi called his attack "unjustified" and vowed to protect its economic interests,