British commanders committed troops to operations in Afghanistan because they feared that the Army would be cut if they did not use them, the Government's former envoy to Kabul has claimed.
Sir Sherard Cowper-Coles said he had been told by the former head of the Army, General Sir Richard Dannatt, that if he did not re-deploy battlegroups coming free from Iraq he would lose them in a future defence review.
In a written memorandum to the Commons Foreign Affairs Committee, he said the Afghan campaign had seen "unprecedented" resources diverted to the Army and that most soldiers appeared to be "enjoying" it.
Sir Sherard said British commanders also saw the mission in Afghanistan as an opportunity to redeem their reputation in the eyes of the Americans after the criticisms of their performance in Basra. "The war in Afghanistan has given the British Army a raison d'etre it has lacked for many years, and new resources on an unprecedented scale," he said.
"In the eyes of the Army, Afghanistan has also given our forces the chance to redeem themselves, in the eyes of the Americans, in the wake of negative perceptions, whether or not they were justified, of the British Army's performance in Basra. Not surprisingly, in a profession paid to fight, most have been enjoying the campaign.
"Against that background, the then Chief of the General Staff, Sir Richard Dannatt, told me in the summer of 2007 that, if he didn't use in Afghanistan the battle groups then starting to come free from Iraq, he would lose them in a future defence review. 'It's use them, or lose them', he said."
Sir Sherard said he believed commanders had "unfairly" blamed ministers for shortages of equipment when they could not reasonably be expected to know the details of the logistics involved in a particular deployment. "As Prime Minister, Gordon Brown was particularly unwise to have allowed the military and the Opposition to criticise him over helicopter availability - a very technical subject which requires years of planning," he said.
At the same time he criticised ministers for their unwillingness to challenge military advice because of their lack of knowledge and for fear that they might be accused in the media of being insufficiently supportive of the troops.
In response to Sir Sherard's comments, a Ministry of Defence spokesman said: "British forces are in Afghanistan for one very clear reason - the UK's national security. Alongside international forces from 48 other nations we are there to prevent al Qaida from again using Afghan territory to plot and launch terror attacks.
"As the Prime Minister and the Secretary of State for Defence have made very clear, Isaf (International Security Assistance Force) now has the right strategy and the resources with which to deliver it and are very clear about the role that UK forces are playing within that strategy."