Vietnam’s state oil company urged the US to let a supertanker pass through an American naval blockade outside the Persian Gulf, saying the shipment is critical to the Asian country’s economy.The very large crude carrier Agios Fanourios I, managed by Athens-based Eastern Mediterranean Maritime, performed a mid-ocean U-turn on Monday at around the point where the US blockade begins. It had only just cleared the Strait of Hormuz, holding 1.99 million barrels of Iraq’s Basrah Medium crude, when it...