The cost of chartering a tanker on the route from the Persian Gulf to China for the first time exceeded one million dollars per day, as the war with the Islamic Republic has sharply reduced the number of vessels currently willing to transit through the Strait of Hormuz.

Based on data from the Baltic Exchange in London, oil tankers carrying oil from inside the Persian Gulf to China were being chartered at a rate of $1.35 million per day on Monday.

According to a Bloomberg report, the main method of exporting Persian Gulf oil has now shifted to transferring barrels via Hormuz and delivering them outside the strait to tankers that do not want to enter the waterway.

Transporting crude oil from the Gulf of Oman to China—without the need to pass through the chokepoint—costs about $644,000 per day.

The charter rate had been about $200,000 per day before the start of the war.