The group has made sweeping gains along Yemen’s Red Sea coast after conducting a large-scale military operation aimed at controlling the Bab al-Mandab Strait.

The waterway, which links the Red Sea to the Gulf of Aden and Indian Ocean, is a busy transit point for crude oil, cars and other manufactured goods.

A surge in the U.S. average price for diesel to an all-time high of $6 a gallon has reinforced concerns about higher global inflation.