Iran-backed Houthi militia in Yemen are making a concerted effort to take full control of the country’s Red Sea coast, threatening to put a choke on another major shipping route. 

The Guardian reports the Houthis have claimed control of the key port of Mocha, in an escalation of their fight with the Saudi-backed government on a scale not seen in years.

If they are successful, it would be particularly disastrous for Saudi Arabia, which has been circumventing the Strait of Hormuz by sending its oil through pipelines to the Red Sea coast, for onward export by ship. But the Red Sea is also the entryway to the Suez Canal, meaning Iran and its proxies, which are already restricting passage through the Strait of Hormuz on the other side of the Arabian peninsula, could exert control over waterways carrying more than 30% of world seaborne trade.

The Guardian says that, by increasing their control of the Red Sea coast south of the port of Hodeidah, the Houthis’ aim to force Saudi Arabia and the U.S. to lift the U.S. blockade on Iranian oil tankers in the Persian Gulf. 

U.S. President Donald Trump on September 9 acknowledged he did not expect the war with Iran to end before the U.S. midterm elections at the start of November.