HMS Prince of Wales pictured in Portsmouth Harbour in February.
CNN  — 

Britain’s largest warship, the HMS Prince of Wales, has been forced to stop on its way to the US following an “emerging mechanical issue” shortly after departure, the Royal Navy has said.

On Saturday, the aircraft carrier left Portsmouth, southern England, en route to join exercises off the east coast of North America.

But it remains off the south coast of England while “investigations into an emerging mechanical issue” are conducted, a spokesperson told CNN on Monday.

On its way out of port, the ship sailed past a music festival during a performance by the British band Sugababes, a video posted on Twitter by the local naval base commander shows.

The ship had been due to depart on Friday but it was delayed due to a technical issue, reports the PA media news agency.

Earlier, the Royal Navy described the endeavor as a “landmark mission to shape the future of stealth jet and drone operations off the coast of North America and in the Caribbean.”

Notable port stops listed by the navy include New York, Halifax in Canada and the Caribbean.

“Taking the HMS Prince of Wales task group across the Atlantic for the rest of this year will not only push the boundaries of UK carrier operations, but will reinforce our close working relationship with our closest Ally,” said commanding officer, Capt. Richard Hewitt, in a statement.

The 65,000 metric ton HMS Prince of Wales is one of two Queen Elizabeth-class aircraft carriers in the British Navy, and currently serves as the command ship of the NATO military alliance.

Sister ship HMS Queen Elizabeth will be deployed to the Mediterranean and Baltic in the fall.

The UK navy calls the pair “the largest and most advanced warships ever built for the Royal Navy.”

According to the Royal Navy, the HMS Prince of Wales can carry 40 helicopters on board and has a flight deck 70 meters (230 feet) wide and 280 meters (919 feet) long.