Gen Sir Richard Dannatt: "We need more troops, more boots on the ground"
Prime Minister Gordon Brown refused a major Afghanistan troop reinforcement against the military's advice, the former head of the Army has said.
Gen Sir Richard Dannatt stood down in August 2009 after repeatedly speaking out against what he said were equipment shortages and poor pay and conditions.
He told the Sun that ministers had to be taken "screaming and kicking" to agree to necessary measures.
Downing Street has denied refusing a request for 2,000 extra personnel.
"Any suggestion that the prime minister has been unwilling to deploy more troops or provide the necessary resources is simply wrong," a Downing Street spokesman said.
"The key point here is that there were 7,800 troops in Afghanistan in the summer of 2007. Now there are over 9,000."
The cabinet is due to sit within the week to consider another request from military chiefs for more troops.
Gen Dannatt told the paper that the military advice since the beginning of this year had been for some 2,000 extra soldiers to be sent to Afghanistan - advice that he makes clear was not taken by the government.
He describes himself as "disappointed" with the support the armed forces were given by ministers over the past three years.
Colonel Richard Kemp: "There's no question more forces are needed, it's where that money comes from"
Gen Dannatt told the newspaper that the military's task was made harder by operating with what he terms "at least part of one arm tied behind one's back".
He added: "The military advice has been for an uplift since the beginning of 2009.
"If the military says we need more troops and we can supply them, then frankly they should take that advice and deploy up to the level we recommend.
"If it means finding more resources and putting more energy in, let's do it.
"If you're going to conduct an operation, you're doing it for a reason - to succeed."
Later, in an interview with BBC News, Dannatt said he believes the government will ultimately take the military's advice.
"Our judgement is that we need more troops and more boots on the ground to do the job effectively," he said.
"The last three conversations I had with the prime minister before I left in the summer, he got it. I'm confident they'll take the right decisions in the next little while."
He added: "Maybe it's taken a little longer for those who have the ultimate decision-making power to realise, perhaps, the military were right on this one."
Shadow defence secretary Liam Fox said: "We now have confirmation of what most of us believed: that, despite all the denials, Gordon Brown was asked for more troops, but turned the request down.
"How can Gordon Brown maintain public support for the war in Afghanistan when he can't even be honest with the British people?"
The number of UK service personnel in Afghanistan has risen in 2009 from 8,000 to just over 9,000.
But many currently serving in Helmand say more boots on the ground are vital - and that initially, they may have to be British until enough Afghan security forces can be trained to take over.
Gen Dannatt's comments come after US Defence Secretary Robert Gates said more time was needed to decide whether to increase troop levels in Afghanistan.
A Ministry of Defence spokesman said the government had long insisted it would review troop numbers after the Afghan election, in the light of military advice, the situation on the ground and the outcome of international discussions.
"Any decisions on future troop levels would be subject to sign off by the Ministerial Committee on National Security, International Relations and Development and discussions with allies," he said.
"The prime minister has been clear that any increase in British troops would need to be conditional on these important factors; the feasibility of being able to send the necessary equipment.
"The right strategy being agreed across the international coalition with all countries signed up and prepared to bear their share of the burden.
"And a new Afghan government in place ready to seize the initiative on corruption, and ready to send more Afghan troops to be trained and partnered by our troops."
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