Spanish Republicans wanted to get rid of foreign submarines in Spanish waters according to the Dutch newspaper Soerabaijsch handelsblad dated 14 June 1937

An item referred to an announcement of radio Bilbao that a new submarine flotilla with modern armament was just commissioned in the Mediterranean with as main task to get rid off all foreign submarines including those of Germany and Italy. This must be Republican submarines.(1)

Note
1. Dutch warships including submarines escorted merchant shipping in Spanish waters during the Civil War.