HMS United (P44) was a Royal Navy U-class submarine built by Vickers-Armstrong at Barrow-in-Furness.

Whilst covering the Allied invasion of Sicily, United spotted the Italian transport submarine Remo on the surface.

Only four survived, the three who were on the conning tower (amongst them the CO, Captain Vassallo), and Sergeant Dario Cortopassi who was able to come up from the control room.

United also sank the Italian transport ship MS Rosolino Pilo, which had already been damaged in a previous attack by motor torpedo boats.

The Attilio Regolo had lost her bow due to an attack the previous day by HMS Unruffled.