The Royal Navy requisitioned three cruise ships during the Falklands Conflict; the P&O ships Canberra and Uganda and the Cunard ship Queen Elizabeth 2 (QE2). Canberra and QE2 would serve as troop transports, while Uganda was used as a hospital ship. Of the three ships, only Uganda had passengers aboard when she was requisitioned. Canberra was requisitioned after returning from a cruise, and QE2 was requisitioned before departing on one.

Canberra was the first of the three ships to be requisitioned. The RN needed to transport 4,350 men of the 3rd Commando Brigade, reinforced by the 2nd and 3rd Battalions of the Parachute Regiment. The Navy's (and the RFA's) amphibious shipping could accommodate 2,650 men, leaving a shortfall of 1,700. On the 3rd April 1982, Canberra was chosen to transport the remaining troops, as she was large enough to carry 2,000-2,400 troops and was available near-immediately. At the time, she was in the Mediterranean, on the last leg of a round-the-world cruise. As she passed Gibraltar on the 5th, a team of naval architects, Royal Marine officers and other officials was put aboard in plain clothes. They would determine her suitability for the role, design the necessary modifications for military service, and allocate space to units. She arrived in Southampton on the 6th-7th and offloaded her passengers. Helipads, military radios, and equipment for refuelling at sea was added over the next two days (though work on the helipads was not complete by the time she sailed, with workmen still aboard working to finish it). Men from 3 Commando Brigade and the Paras were loaded, and she departed on the 9th. Her departure was not secret. Passengers who had booked to sail on her next cruise would receive telegrams warning them that their holidays had been delayed indefinitely. Her sailing was televised, and she sailed with what the Official History describes as 'much excitement ashore'.

Uganda was, in peacetime, used for schools cruises, carrying school children on educational cruises. She was requisitioned on the 10th to serve as a hospital ship - the other main candidate, the Royal Yacht Britannia, was too small to sustain the expected needs of the Task Force, and would be the only ship in the force using fuel oil rather than diesel. On the 10th, she was in harbour in Alexandria, carrying 944 children and their teachers. On the 11th, she steamed to Naples, where her passengers were offloaded. They would fly home, losing five days of their cruise. Uganda would then sail to Gibraltar, where she would spend 65 hours in the dockyard there. The refit added surgical facilities, water distillation equipment and helipads. She would also be repainted in the livery of a hospital ship, with white paint and large red crosses. She sailed from Gibraltar on the 19th, again in a well-publicised departure.

As the war progressed into May, it became necessary to send another brigade to the South Atlantic. 5th Infantry Brigade was chosen for the role. With the RN's sealift forces entirely engaged in the South Atlantic, 5 Brigade had to be carried by requisitioned ships. QE2 was the obvious choice, as she was the only large British cruise ship available, capable of carrying ~3000 men. Every other option was either much smaller, or was under foreign ownership. QE2 was requisitioned on the 4th May, just after she had returned from a trip to the United States. While there was no need to offload passengers, she was just about to depart on a trip to the Mediterranean with a full load of passengers. The requisition order came through just 19 hours before her departure. Once again, the prospective passengers found their trips cancelled with little fanfare. Other sailings planned for the rest of the summer were cancelled or deferred. QE2 underwent a refit similar to those undergone by Canberra and Uganda, though it was considerably less hurried. She sailed on the 12th May, with crowds on the quayside watching her depart.