Britain's biggest warship has been spotted off the coast of Portland Bill today as it conducts training with the RAF.

The Royal Navy aircraft carrier, HMS Prince of Wales, is serving as a NATO Command Ship, ready to deploy in support of NATO exercises and operations throughout the year.

Having raised the NATO flag earlier this month ready to act as the alliance’s command ship throughout the year, the ship’s company are working with Fleet Air Arm and RAF aviators to prepare for operations later on.

A spokesman for the Royal Navy said that people on the Dorset coast, especially around Portland and Lyme Regis, were likely to have seen the ship over the weekend.

He said: "The ship is conducting training with RAF Chinooks from Odiham and also Navy Wildcat helicopters from Yeovilton.

"There are no plans to use the [Portland] harbour, although they might be conducting boat transfers."

Training by the helicopter squadron from RAF Odiham in Hampshire has been taking place on the warship. Three Chinooks are embarked on the carrier as their aircrew earn deck qualifications deeming them safe to operate from Prince of Wales by day and night.

As well as the RAF, the ship has been joined by Wildcats of the Fleet Air Arm’s 825 Naval Air Squadron, also getting their sea legs in home waters.

The Yeovilton-based squadron feeds its sister front-line unit, 815, with trained air and ground crew to provide helicopter flights for destroyers and frigates operating around the globe.

Crews have been practising general duties operating from the carrier’s deck, as well as winching and load lifting.

Once her work-up for NATO command ship duties are complete, Prince of Wales is due back in Portsmouth next month when she’ll prepare for her debut in the High North.

The carrier was declared fully operational at the beginning of autumn following two intensive years of trials and training.

Her flight deck is 70 metres wide and 280 metres long - on which 40 helicopters can be carried and embarked. She has a minimum crew of around 700, increasing to around 1,600 with aircraft onboard.