New Delhi, Aug. 20 -- US President Donald Trump has threatened to escalate the pressure on Iran from the battlefield to the global economy, warning countries and businesses that continue providing Tehran with financial or commercial support could face severe US penalties.

Trump described the planned measures as an "ECONOMIC D-DAY" and threatened what he called "Economic Warfare and Isolation on an unprecedented scale." However, he did not specify exactly what new measures Washington would impose or which countries would be targeted.

The threat comes after weeks of US and Israeli military strikes and a US maritime blockade have failed to force Tehran to capitulate. It also puts the spotlight on China, Iran's biggest buyer of oil, and cou...