HMS Prince of Wales could miss 'landmark mission' with fighter jets and drones as Royal Navy scrambles to fix propeller fault

Britain's biggest warship could miss important tests involving the latest fighter jets and drones after a propeller shaft malfunctioned a few miles after it set sail.

The £3bn HMS Prince of Wales aircraft carrier left Portsmouth on Saturday but a "mechanical fault was discovered with the starboard shaft", said Rear Admiral Steve Moorhouse.

Its journey to the US had barely got going before the ship was forced to crawl back to Hampshire, accompanied by tugs, from a position off the Isle of Wight.

Divers will be able to use a sheltered bay, believed to be at Gosport, to assess the problem - which specialist news site Navy Lookout called a "significant technical fault".

Rear Admiral Moorhouse said in a video statement on Twitter that it was "likely that the fault will require repairs which may impact the ship's programme".

He said more details on the problem and the disruption to the ship's schedule would be given after further inspection is carried out.

"We've reacted quickly to the emergent defect and are working closely with industry partners to resolve this as soon as we can," said Rear Admiral Moorhouse - who is responsible for ensuring Royal Navy ships are ready to be deployed.

HMS Prince of Wales acts as NATO's command ship and was heading to North America for exercises with the US and Canadian navies and the US Marine Corps.

Fifth-generation F-35B Lightning jets and Banshee drones were expected to operate off its deck and its itinerary included New York, Halifax in Canada and the Caribbean.

The Royal Navy had described it as a "landmark mission".

Its breakdown just after setting off is an embarrassment for the Royal Navy, especially as the 280-metre ship only became operational last year.

The vessel's departure had earlier been delayed from Friday because of a technical issue, although it is not known if the incidents were related.

HMS Prince of Wales can carry 36 F-35B Lightning jets and four Merlin helicopters, with a crew of about 700, increasing to 1,600 when all aircraft are onboard.

The jets were due to join the ship in the US.