Ferrini did not tolerate this independence; he accused Borghese of having contacts with the Allies and the anti-Communist partisans, and of conspiring to depose Mussolini and replace him at the head of the RSI.

Part of the personnel recruited by the MNR served on Kriegsmarine ships in the Mediterranean, whereas others manned coastal batteries in Northern Italy.

[3] Other personnel fought on land alongside the National Republican Army and the Wehrmacht The Marina Nazionale Repubblicana only reached a twentieth the size of the Allied Italian fleet,[5] and consisted of nine motor torpedo boats (two large and seven small), dozens of MTSM small motor torpedo boats and MTM explosive motorboats.

[9] Of their CB midget class submarines, five were initially given to the Italian Social Republic by Germany,[10][11][12] but later ten more boats were transferred by the Germans to the RSI Navy and served in the Adriatic.

[14] The only success by a MNR vessel came on 16 April 1945, a few weeks before its dissolution, when one MTM hit and heavily damaged the French destroyer Trombe off Liguria, Italy.