Nuclear-powered Royal Navy sub 'in warzone' with capacity to strike

A nuclear-powered Royal Navy submarine has arrived in the Arabian Sea – and with it the capacity to launch cruise missile attacks, military sources claim.

HMS Anson, which is fitted with Tomahawk Block IV land-attack missiles with a range of 1,000 miles and Spearfish heavyweight torpedoes, left port in Perth on March 6 and is believed to be taking up position in the deep waters of the northern Arabian Sea.

It would mean British forces have the capacity to launch attacks on Iran if the conflict escalates.

The news comes after Downing Street said on Friday that Sir Keir Starmer had agreed to allow the US to use British bases to launch strikes on Iranian sites that have been targeting the Strait of Hormuz. 

Sir Keir had previously allowed US forces to use the bases only for defensive operations, to prevent Iran firing missiles that put British interests or lives at risk.

However, he has now approved an expansion of the targets to help protect ships in the shipping channel on the basis of 'collective self-defence'.

HMS Anson, which has travelled 5,500 miles from the west coast of Australia to await orders, rises to just below the surface every 24 hours to allow it to communicate with the UK's military bunker at the Permanent Joint Headquarters (PJHQ) in Northwood, London.

Defence sources said that at PJHQ, Lieutenant General Nick Perry, the chief of joint operations, would give the order to fire if authorised by the Prime Minister. 

HMS Anson would then rise close to the surface and dispatch a salvo of four missiles.

The state-of-the-art submarine, based at Faslane in Scotland, does not have a standard periscope and instead shows views of the surface on a huge television screen.

Its nuclear reactor means it will not need to be refuelled during its 25-year service, while its ability to purify water and air means it can circumnavigate the planet without resurfacing.

This, however, is limited by the fact that the vessel is only able to carry three months' supply of food for 98 officers and ratings.

A source said: 'Anson will be quietly lurking. The Prime Minister and Commander Maritime Operations will be told where she is and, of course, the Submarine Service – but her location won't be widely known.

'The Navy dashes submarines into place and can then leave them sitting there for weeks.

'If necessary, she will be running silently, so no showers, no flushing loos and many men washing in one sink of water. It gets very smelly.'

The Ministry of Defence declined to comment today on the location of HMS Anson.

A spokesman said: 'We won't provide running detail on specific operations or deployments.

'We keep our capability in the region under constant review.'