Oil giant Saudi Aramco has been looking to secure thousands of tons of diesel in the Mediterranean after a series of attacks on its energy facilities over the past few weeks. The pickup in activity predates attacks last week on a pipeline that feeds oil refineries on the kingdom's Red Sea coast, but coincide with reported incidents involving the fuel-making plants over the past few months. Sometimes companies will buy replacement cargoes if their normal source of supply isn't available.

The move underscores the volatility in regional energy supplies and Aramco's efforts to mitigate disruption risks.