US crude oil exports to Asia are set to hit multi-year lows after the Iran war disrupted global shipping and pushed the cost to lease a tanker for the Pacific journey to a record of almost $80 million.

Dense heavy crude, which oil refiners around the world favor for its typically low cost, is piling up in the Americas as soaring freight rates have stifled exports and US refiners have been running close to their limits. 

For a sign of just how extraordinary oil shipping costs have become, consider this: It’s now more expensive to hire a tanker from the US to China than to launch a rocket into space.