Gordon Brown: ''We must persist with our operations in Afghanistan''
Gordon Brown has insisted Britain has the resources "to do the job" in Afghanistan, amid claims troops serving there are under-equipped.
The prime minister told MPs helicopter numbers had increased 60% since 2006 and UK forces were the best equipped they had been in 40 years.
Tory leader David Cameron attacked the "scandal" of helicopter shortages.
UK forces in Afghanistan will also hold a memorial service later for eight men who died in a single 24-hour period.
Tributes will be paid at Camp Bastion, a day after it emerged that three of those killed on Friday were just 18.
Five of those who died on Friday were members of the County Down-based 2nd Battalion The Rifles. They were: Cpl Jonathan Horne, and Riflemen Joseph Murphy, Daniel Simpson, William Aldridge and James Backhouse.
The sixth was Cpl Lee Scott, of the 2nd Royal Tank Regiment.
In the same 24 hours - the bloodiest since the start of operations in Afghanistan in 2001 - Rifleman Daniel Hume, of 4th Battalion The Rifles, and Pte John Brackpool, 1st Battalion Welsh Guards, also died.
The British armed forces are better equipped today than they have been at any time in 40 years but we are not complacent
In a Commons statement Mr Brown told MPs: "It has been a very difficult summer and it is not over yet but if we are to deny Helmand to the Taliban in the long term, if we are to defeat this vicious insurgency, and by doing so make Britain and the world a safer place, then we must persist with our operations in Afghanistan."
But he added: "I am confident that we are right to be in Afghanistan, that we have the strongest possible plan and we have the resources needed to do the job."
The Tories have accused the government of the "ultimate dereliction of duty" in under-equipping the armed forces.
In his statement, Mr Brown said troop levels were kept under review but he had been assured by commanders on the ground, and top level military chiefs, that they had the manpower needed "for the current operations".
He said he had urged Afghanistan's president Hamid Karzai to make more Afghan personnel available, to help hold ground secured by forces in Helmand.
David Cameron: ''Beg, borrow, or frankly steal those helicopters"
Funding for operations in Afghanistan had increased from £700m in 2006-7 to more than £3bn this year and all "operational requirements" would be met, he said.
Helicopter numbers had increased by 60% in the past two years and, by increasing crews and equipment their capability - or flying hours - had increased by 84%.
More equipment, including Merlin helicopters and Ridgeback armoured vehicles, were being brought in and eight Chinooks used in Iraq were being converted to cope with Afghanistan's weather and terrain.
"As the chief of the defence staff has said, the British armed forces are better equipped today than they have been at any time in 40 years but we are not complacent," he said.
"We are striving daily to have the best equipment available for our troops in Afghanistan."
He said the government would "continue to give safety the highest priority" and said he had been assured Operation Panther's Claw was having a "major impact on the Taliban".
All party leaders paid tribute to those killed in recent days - Mr Brown said Britain owed them a "huge debt of gratitude".
Conservative leader David Cameron said more needed to be done to set out a "tightly defined, hard headed and realistic" strategy.
He pressed the prime minister on whether he had turned down a military request for an extra 2,000 troops.
Eight British soldiers were killed in just 24 hours last week
And he said while Mr Brown had said helicopter capacity had increased since 2006 the "real point" was that the number of troops had doubled since then.
"So proportionately there hasn't really been an increase in helicopter capacity at all," he said.
"Do you regret the £1.4bn cut in the helicopter programme that you as the chancellor of the exchequer pushed through in 2004?"
Mr Brown quoted the spokesman for the task force in Helmand, Lieutenant Colonel Nick Richardson, as saying they had the "proper equipment", that it was "first rate" and had pointed out it was a "sad fact that helicopters would not have saved the lives" of the soldiers killed last week.
At a press conference earlier Mr Cameron said it was a "scandal" that troops "still lack enough helicopters to move around in Afghanistan".
He said other Nato countries should fulfil their commitments, arguing that the government needed to "really hold their feet to the fire" and "beg, borrow or frankly steal the helicopters that are necessary".
In the Commons Liberal Democrat leader Nick Clegg criticised British strategy in Afghanistan as "over-ambitious in aim and under-resourced in practice".
He said Britain must not overreach itself "by trying to import overnight a Western-style democracy in a country that has never had a functional government" and instead aim to stabilise Afghanistan "to provide a space for the state to grow".
He also urged Mr Brown to send "desperately needed" helicopters to British troops.
Nick Clegg called for ''a reasonable goal'' in Afghanistan
A poll carried out for the BBC and the Guardian suggests public opinion is split over the UK's mission in Afghanistan.
Of 1,000 people questioned, 47% said they opposed the British operation, while 46% said they supported it.
However in 2006 only 31% of those polled gave their support.
An offensive designed to increase security ahead of Afghan elections next month has seen a big increase in UK casualties, with 15 servicemen killed in the first 10 days of the month.
It means 184 service personnel have now died in Afghanistan since 2001, more than the 179 who were killed during the war in Iraq.
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