Iran is discreetly scouring the globe for second-hand oil tankers to replace its ageing fleet and keep crucial crude exports flowing as U.S. sanctions start to bite, Iranian and Western sources said.  Since U.S. President Donald Trump reimposed sanctions in November, exploratory talks with South Korea for up to 10 new supertankers have stalled, Panama has removed at least 21 Iranian tankers from its registry and Tehran is now looking for extra vessels in places such as Vietnam, the sources said. Washington has put restrictions on Iran’s port, energy and shipping sectors but it has given waivers to the country’s eight biggest oil customers, which include China, India and Japan, so they can keep […]