Afghanistan could again become a haven for terrorists like al Qaida after international forces have pulled out in three years' time, the head of the British armed forces has acknowledged.
General Sir David Richards, the Chief of the Defence Staff, insisted that stabilising the country in time for the planned final handover to Afghan security forces in 2014 is "do-able".
On the 10th anniversary of the international military intervention in Afghanistan, he told ITV News that the coalition had plans to ensure the country did not revert to an enclave for al Qaida.
But pressed if it could again become a safe haven for terrorists, he replied: "Well it could... but if our plan is successfully implemented, and I've every reason to think they will be and we're talking another three-and-a-half years or over three years, then there's no reason to think it will deteriorate into that sort of place that your worst imagination is getting at."
It is expected the Americans will retain a relatively small counter-terrorism force in Afghanistan after 2014, although UK ministers have insisted that there will be no British troops engaged in major combat operations.
Gen Richards said that ensuring they left a stable Afghanistan was essential to Britain's own long-term national security.
"I think we've got to be clear that we're not talking about creating a Switzerland in that part of the world," he said.
"We're talking about a country that can look after itself. The reason it's important to us is because a stable Afghanistan is vital to our own long-term security. I think it is do-able."
Meanwhile, retired US Army General Stanley McChrystal claimed America and its Nato allies were barely over half way to reaching their goals in Afghanistan.
Gen McChrystal, who commanded coalition forces in 2009-10, said that even after a decade, they still lacked the knowledge to bring the conflict to a successful end.