More than 5,700 British troops will be sent on a three-year mission to Afghanistan at a cost of a billion pounds, the Government has announced.
Five years after the Afghan war, a British force - larger than the one in that campaign - will be back on the frontline of an intensifying conflict, which has seen a resurgent Taliban and al-Qa'ida carry out waves of attacks, including suicide bombings.
The deployment to Afghanistan , mainly centred on Helmand province, is almost three-quarters of the strength of the British forces in southern Iraq.
Government plans for a substantial withdrawal from Iraq before sending forces to Afghanistan have been shelved because of continuing turbulence. But John Reid, the Secretary of State for Defence, insisted yesterday that carrying out both operations simultaneously was "manageable".
Critics have accused the US and Britain of failing to stabilise Afghanistan before moving the "war on terror" on to Iraq. Following the Afghan war, Tony Blair declared, "this time we will not walk away" - a reference to the way the West backed Afghanistan in the Cold War against the Russians, but left the country to the anarchy of feuding warlords.
Ministers maintain that the mission will primarily help with reconstruction and the training of Afghan government forces. However, it was acknowledged that British troops are likely to come under attack.
As well as infiltration by Islamist fighters from Pakistan, the Helmand province has the largest concentration of opium cultivation, controlled by warlords.
The International Development Secretary, Hilary Benn, said: " The indiscriminate killing of teachers and aid workers in Helmand shows the very real danger ... we go into this with our eyes open." But the Government stressed that action was essential to help the Afghan President, Hamid Karzai.
Mr Reid said a failure to act would result in further terrorist attacks like those of 11 September 2001.
The task force will include paratroopers from the 16 Air Assault Brigade and the 3rd Battalion, the Parachute Regiment, supported by Apache helicopter gunships.
They will be supported by a recce squadron of Scimitar and Spartan armoured vehicles from the Household Cavalry, a battery of light guns from 7th Parachute Regiment, Royal Horse Artillery, and Desert Hawk unmanned aerial drones from 32 Regiment, Royal Artillery.
An RAF Harrier detachment, based in Kandahar, will provide a report before being replaced by planes of the Netherlands air force.
The British force will form the core of a 9,000-strong Nato brigade taking over from the US in south-east Afghanistan. The Dutch parliament is still to ratify the deployment of 1,400 troops due to join the British force.Reuse content