A draft budget for the additional ship has been submitted to parliament for approval, he said at the Rheinmetall yard, according to German media reports.
Pistorius said the ships can pick up signals and sounds that other vessels cannot. He described them as vital tools for building a clearer picture at sea, adding that they collect and evaluate a wide range of maritime signals.
German officials have long argued that the navy needs better tools to monitor the Baltic Sea, where undersea cables and energy links have been damaged and Russian military activity has risen since the Ukraine war began in 2022.