British troops are pulling out of Sangin, the most lethal place in the Afghan frontline, where they had suffered nearly a third of their fatalities in the war.
The Independent has learned that US troops will take over control of the town which has become of symbolic as well as strategic significance to both the Western alliance and the Taliban in the fierce conflict.
The announcement of the transfer of command is due to be made in London by the Defence Secretary, Liam Fox, and in Kabul, by General David Petraeus, the American commander of Nato forces in Afghanistan, today. The plans for the handover had been drawn up under General Stanley McChrystal before he was sacked.
The news of the withdrawal will come almost four years to the day when the 3rd Battalion, the Parachute Regiment went into Sangin after pressure from the Afghan president, Hamid Karzai, sparking fierce clashes with insurgents. The battalion was due to return to Sangin in the autumn, but is now expected to deploy the central Helmand belt of the provincial capital, Lashkar Gar, Nad-e-Ali and Gereshk.
Troops from 3 Para and the British forces following them won numerous honours for bravery and pushed back the Taliban lines. However, a high price came with the advances – of the 312 members of British forces killed in Afghanistan since 2001, 97 have died there, most from a relentless IED (improvised explosive devices) campaign.
The move from Sangin is expected to lead to criticism from some quarters, with analogies being drawn with Basra, from where British troops pulled out forcing the US marines to take over. There are also likely be complaints that "blood and treasure" (lives and financial investment) expended by the UK have been wasted.
But the UK military and diplomats yesterday robustly denied these charges, stressing that the move was driven by strategy on the ground and it was anomalous to have such large numbers of British troops in an area under American control.
A senior British military officer said: "This change makes perfect military sense. Our troops have done a fantastic job in one of the most dangerous parts of Helmand and the US can build on this now. We will leave with our heads held high and proud of what we have achieved."
The withdrawal will also benefit the British Government with the numbers of deaths being reduced. That in turn, hope the military commanders, will help in reducing the clamour among some politicians for a timeline for withdrawing UK forces from the war.
The Independent revealed two months ago how UK forces in Helmand were moving under American control as part of a radical restructuring plan with the command in southern Afghanistan being split in half.
Helmand has been divided under this command with previously British-controlled towns like Musa Qala and Kajaki being transferred to the Americans. UK forces will focus on population centres where reconstruction projects are taking place.
Sangin, however, has special resonance because of the sheer scale of the violence and losses suffered.
The town and its hinterland is part of a feeder route into the Helmand river valley and Lashkar Gar where young jihadists cut their teeth. At the same time, some of the Taliban's most proficient bomb makers are based there and the surrounding area contains rich opium fields providing revenue which feeds the insurgency.
Royal Marines from 40 Commando lead the current battlegroup in Sangin. Lieutenant Colonel Paul James, the commanding officer, said after the latest losses: "We owe it to the sacrifice these brave marines have made to remain entirely focused on our mission; to protect the people of Sangin in partnership with the Afghan army – and we shall.
"The Taliban cannot win as they offer only violence and intimidation, and the people of Sangin know it. Even in the most pro-Taliban of areas there is only 20 per cent support for their cause. It is slow, hard and often painful but we are making progress here."
Major-General Richard Mills, the US commander in Helmand, said that the UK forces' performance had been "simply nothing short of magnificent".
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