Key role for UK armed forces

HMS Trafalgar, which was in action on Sunday

British armed forces are heavily involved in the attack on Taleban forces in Afghanistan.

Three nuclear submarines - HMS Trafalgar, HMS Triumph and HMS Superb - took part but the Ministry of Defence will not specify which vessel launched cruise missiles against targets in Afghanistan from the Indian Ocean.

HMS Superb does not carry cruise missiles and would have been involved in an auxiliary capacity.

Trafalgar and Triumph, both nuclear-powered subs, are hunter killer vessels and do not carry nuclear warheads.

Renowned for stealth

They are renowned for their stealth, endurance and ability to act independently.

Each sub has a crew of around 100, weighs around 5,000 tonnes and is about a third of the size of the giant Kursk submarine which sank in the Barents Sea last year.

There is no greater strength for a British prime minister and the British nation at a time like this to know that the forces we are calling upon are amongst the very best in the world.

Tony Blair

HMS Trafalgar and HMS Superb are both armed with Tomahawk Land Attack Cruise Missiles.

Prime Minister Tony Blair said there were three main areas in which the UK was helping: the submarines, reconnaissance and other aircraft; and the use of the British-owned airstrip at Diego Garcia in the Indian Ocean.

The prime minister said: "Last Wednesday the US Government made a specific request that a number of UK military assets be used in the operation which has now begun and I gave the authority for these assets to be deployed."

He said the submarines had been used on Sunday while the other facets would be available in the next few days.

Base for B-52s

It is understood US B-52 heavy bombers have been sent to Diego Garcia, a British Territory in the Indian Ocean, and would be involved in bombing of targets in Afghanistan.

B-52s are capable of travelling thousands of miles without refuelling and were widely used in the 1991 campaign against Iraq.

Mr Blair mentioned reconnaissance "and other aircraft" but did not go into specific detail about which aircraft were being used.

Tornado fighter-bombers are based in Oman and Harrier fighters are stationed on Royal Navy warships in the area.

The RAF also has Hercules and Nimrod transport aircraft and a large number of Chinook and Puma helicopters in Oman for the Operation Saif Sareea exercise.

About 24 British Royal Navy warships - led by flagship aircraft carrier HMS Illustrious - are in the region and approximately 23,000 British troops are in Oman for war games.

But none of these were among those "assets" deployed by Mr Blair.

Mr Blair said: "I want to pay tribute to Britain's armed forces. There is no greater strength for a British prime minister and the British nation at a time like this to know that the forces we are calling upon are amongst the very best in the world."

'Held in high esteem'

He said: "They and their families are of course carrying an immense burden and will be feeling immense anxiety but we can take pride in their courage, their sense of duty and the esteem with which they are held throughout the world."

Mr Blair said he had no doubt the 11 September attacks were carried out by Osama Bin Laden's Al Qaeda network, and that it was harboured and supported by the Taleban regime.

He said an ultimatum, demanding the Taleban give up Bin Laden, had expired two weeks ago and added: "They were given the choice of siding with justice or siding with terror and they chose to side with terror."