South Africa said it’s evacuating researchers at a sub-Antarctic Marion Island base after the Iran war delayed fuel deliveries needed for the operations.

The “urgent evacuation of the overwintering team” was ordered after the SA Agulhas II, an icebreaking polar-supply ship, got held up in Cape Town for weeks waiting for the fuel, the Department of Forestry, Fisheries and the Environment, said in a statement late Thursday. The station requires polar diesel that doesn’t freeze in extreme cold.