London, Aug 30 (IANS): The UK's Royal Navy aircraft carrier HMS Prince of Wales is limping back closer to shore after breaking down off the Isle of Wight shortly after setting out for exercises off the US coast.

The 65,000-tonne warship left from Portsmouth Naval Base on August 27 before an "emerging mechanical issue" occurred, reports dpa news agency.

The departure of the 3 billion pounds ship had already been delayed from August 26 because of a technical problem, although it is not known if the incidents are related.

Specialist website Navy Lookout said the issue was caused by damage to the starboard propeller shaft, although the Ministry of Defence has not commented on this.

The website said a photograph of the carrier leaving Portsmouth shows a wake only on the port side, suggesting a problem with the other propeller shaft.

It added that unless the problem can be resolved at sea the warship might need to go into dry dock at Rosyth, Scotland, months ahead of a planned inspection in 2023.

The carrier was moving slowly from south east of the Isle of Wight towards Stokes Bay, Gosport, on Monday afternoon where it is understood the sheltered area will make it easier for divers to examine the damage.

A Royal Navy spokeswoman said: "HMS Prince of Wales remains in the South Coast Exercise Area while conducting investigations into an emerging mechanical issue."

The carrier had a colourful send-off as it departed on August 27 afternoon and passed thousands of music-lovers at the Victorious Festival on Southsea Common in Portsmouth.

The NATO flagship is sailing to undertake training exercises with the US Navy, the Royal Canadian Navy and the US Marine Corps.

The programme is expected to include exercises with the F-35B Lightning jets.