British steam tanker Lunula visited the Black Sea according to a letter of the German naval attaché at Istanbul dated 17 February 1940

In his letter dated Istanbul, Turkey 17 February 1940 No. 758 g. reported the German naval attaché to the Oberkommando der Wehrmacht Abteilung Ausland the neutral ships passing Istanbul coming out of the Black Sea and loaded with contraband for or chartered by the enemy. An item reported on 12 February 1940 the British steam tanker Lunula with 9,215 ton gasoline underway from Constanta, Romania towards Gibraltar for orders.

Source

Bundesarchiv. German Marineattaché for Greece, Romania and Bulgaria 1939-1941. RM 12-II/459.