Allied Forces assembled to meet the Italian Fleet

BB Warspite
BB Valiant
BB King George V
DD Faulknor
DD Fury
DD Echo
DD Intrepid
DD Raider
DD Vasilissa Olga (Greek)
SD Le Terrible (French)

Italian Forces

From La Spezia
BB Roma*  9th Division
   Vice-Adm. Carlo Bergami – Fleet Cmdr.
BB Vittorio Veneto 9th Division
BB Italia (ex-Littorio) 9th Division
CL Eugenio di Savoia  7th Division   Rear-Adm. Romeo Oliva – Div. Cmdr.
CL Duca d’Aosta 7th Division
CL Montecuccoli 7th Division
DD  Mitragliere 12th DD Flotilla
DD Fuciliere 12th DD Flotilla
DD Carabiniere 12th DD Flotilla
DD Velite  12th DD Flotilla
DD Legionario 14th DD Flotilla
DD Oriani  14th DD Flotilla
DD Artigliere 14th DD Flotilla
DD Grecale  14th DD Flotilla

From Genoa
CL Abruzzi  8th Division
CL Garibaldi 8th Division
CL Regolo  8th Division   Captain Marini ?
TB Libra

From Castellamare
DD Da Noli*
DD Vivaldi*

From Taranto
BB  Caio Duilio 5th Division
   Vice-Adm. Alberto Da Zara – Div. Cmdr.
BB Andrea Doria 5th Division
CL Cadorna
CL Pompeo Magno
DD Da Recco

From Pola
BB Giulio Cesare 5th Division   Commander Vittore Carminati
(Cesare was under repair and sailed with a reduced crew)

From other Adriatic ports
Seaplane Tender  Miraglia
DD Riboty
TB  Sagittario

* sunk

Except for the Italian warships mentioned in note #1 below, all of the aforementioned warships proceeded to Malta in accordance with the terms of the Armistance.
 

Notes:
1.  After Roma’s loss, the torpedo boats Libra, Orione, Orsa, Impetuoso, and Pegaso were summoned to pick up survivors along with the cruiser Regolo & destroyers Mitragliere, Fuciliere, and Carabiniere.  Pegaso and Impetuoso were sunk in a collision after the rescue operation.  Libra and Orione proceeded to Bone with survivors.  Regolo, Mitragliere, Fucliere, Carabiniere and Orsa ended up at Port Mahon in the Balearics and were interned for the rest of the war.

2.  Other surrendered Italian units, including 33 submarines, 11 torpedo boats, 8 corvettes, and other smaller warships, reached Italian ports that were in Allied control.

Sources:
1. Chronology of the War at Sea 1939-1945 by J. Rohwer & G. Hummelchen
2. The Naval War in the Mediterranean 1940-1943 by J. Greene & A. Massignani
3. The Italian Navy in WWII by A. Bragadin