UK troops in Sangin did not die in vain, says Cameron
UK troops killed in Afghanistan did not die in vain, David Cameron has said as a four-year mission in Sangin ended.
The prime minister said British troops had performed "magnificently" in the area of Helmand province which had seen the UK's heaviest losses.
Of the 337 UK deaths since 2001, a third have happened in Sangin.
The UK has handed responsibility for security there to US forces, with 1,000 Royal Marines and other personnel redeployed to central Helmand province.
Mr Cameron said: "Look, these decisions are never easy, but this is the right decision. We should share the burden properly with our allies, we should concentrate our forces where they can have the maximum impact.
After five bloody summers in Sangin, British troops have handed over control to the men of the US Marine Corps and begun pulling out.
A third of all UK deaths in Afghanistan have taken place here in a district that is as important as it is dangerous.
The Americans have already changed the strategy on the ground, pulling out of some patrol bases that the British fought hard to establish and protect.
The terrain, its location at the cross-section of key routes and a thriving opium trade have made it a key battleground for both the insurgents and British troops.
Military commanders insist this is not a case of America coming to the rescue of beleaguered UK forces, but the handover will be a bittersweet moment for the thousands of troops who have fought so hard in Sangin over the past four years.
"Our troops have performed magnificently in Sangin and I pay tribute to the thousands who have served, to the over 100 who've given their lives and to the many who have been wounded.
"They did not die in vain, they made Afghanistan a safer place and they have made Britain a safer place and they will never be forgotten.
UK forces have been in the area since 2006, and 106 UK personnel have been killed, 36 during this year alone.
The Ministry of Defence (MoD) announced in July that British troops were to be replaced by US forces.
Control was formally handed over from UK forces to the US Marine Corps at 0630 BST.
Defence Secretary Dr Liam Fox said British forces had gallantly and tenaciously fought for a better life for locals in Sangin and for increased security.
He said the handover to coalition partners made operational and tactical sense and that he was "immensely proud" of all those who served in Sangin since 2006.
He also paid homage to those who made the "ultimate sacrifice" there.
"This handover will create a proper force density ratio for counter insurgency operations in Britain's area of responsibility and will better prepare us for the difficult months we will face in Helmand," he said.
Lt Gen Nick Parker, deputy commander of Nato forces in Afghanistan, said the move was a "routine piece of battlefield relocation" and more "coherent from a tactical, military perspective".
- Most dangerous place for foreign troops in Afghanistan
- Difficult terrain for troops - warren of dirt tracks often too narrow for vehicles
- Easy bomb-planting territory for Taliban and good cover for snipers
- Mix of rival tribes complicates local politics
- Northern Helmand district is at heart of opium-growing industry
The BBC's Ian Pannell in Kabul said there would be a physical handover, with the union jack lowered and the US flag raised, but little would change on a practical level.
He said some members of the 40 Commando Battle Group had already left, and the handover would be staggered over the coming weeks.
Describing it as a "totemic" moment for the UK, he said Sangin was the most dangerous district in Helmand - if not the whole of Afghanistan.
On a recent visit to the area, he witnessed a long battle in which a number of US soldiers, Afghan soldiers and civilians sustained injuries.
"Although progress has been made, the area remains very difficult. It is a key battleground for insurgents and coalition forces.
"The truth is, the Americans will now have to try and finish the job that Britain started," he added.
Ian Sadler, whose son Jack was killed when a landmine exploded underneath his army Land Rover near Sangin in 2007, said he was glad troops were getting out of the area.
"We are pulling out of a hotspot. It's a particularly dangerous area of Afghanistan, so it's a good thing," he told the BBC.'Poignant moment'
"I think it is a shame that while our soldiers were in Sangin they did not have the best vehicles that could have been provided and I still don't think there's enough helicopters."
The former serviceman said it was part of a soldier's job to keep moving on.
"They will be sad for the ones who have been killed, for those who have lost their arms and legs," he added. "But Sangin is like staying at a bad hotel - you're glad when you don't go back."
Col Stuart Tootal, former commander of 3 Para, the first battle group sent into Sangin, says the area will always be significant for British forces.
"We can't ignore the emotion the British are going to attach to Sangin. I mean my own battle group went in there four years ago and half our casualties were lost in Sangin," he said.
The handover "makes pragmatic good sense because it allows the British to focus on their main effort in the centre of the province," he added.
MoD spokesman Maj Gen Gordon Messenger, a former commander of the UK Helmand task force, said it was "absolutely not" a pull-out .
While progress had been slower in Sangin than in other parts of Helmand, he admitted, British efforts had not been worthless.
"It's a hugely important point that the Afghan flag flies in the district centre of Sangin, and that the people of Sangin and the surrounding area recognise that and see the benefits of it," he said.
The commanding officer of 40 Commando group, Lt Col Paul James, said the handover was a "poignant moment" tinged with sadness, but the overwhelming emotion was one of pride.
"I think we've achieved significant success here, making Sangin a much more stable and peaceful place.
Lt Col Clay Tipton, from the US Marine Corps, said UK and US troops had been working together in Sangin for the past couple of months, and their job now was to "continue the success".