Crude tanker rates have risen to levels not seen for 18 years with more expected to come after a “bonkers” week that saw charterers scrambling for tonnage before a European Union ban on Russian imports.

Midsize tankers led the charge owing to a perfect storm of high demand, shortage of ships and port delays caused by poor weather conditions, according to brokers.

European refiners have been forced to look further afield for crude — such as the US Gulf Coast, Brazil and Guyana — boosting voyage distances and driving up tonne-mileage.