Defence chief Sir Jock Stirrup was forced to defend the Government today following the release of the killed officer’s warning over helicopter shortages.

A memo sent by Lieutenant-Colonel Rupert Thorneloe, 39, three weeks before he was killed by a roadside bomb, claimed the force’s lack of helicopters was putting soldiers' lives at risk.

The leaked document has placed fresh pressure on the Government over claims they are not providing sufficient support and equipment for the troops fighting in Afghanistan.

Today, Air Chief Marshall Sir Jock Stirrup tried to play down the suggestion that a lack of helicopters was costing lives.

He warned that helicopters were not a “panacea” solution and that continuing ground patrols were essential in fighting the Taliban.

He said: “You cannot conduct a counter-insurgency from behind metal." Sir Jock added that Colonel Thorneloe, the most senior officer to die in the war, had been criticising the deployment of aircraft within Afghanistan.

"The key element of criticism was inflexibility of allocating helicopter assets within theatre, which to Rupert didn't seem to make sense.

“There is no such thing as enough support helicopters. You can always use more. We are providing the maximum we can, as rapidly as we can.”

Colonel Thorneloe, the commanding officer of the 1st Battalion, Welsh Guards, was killed on July 1, along with Trooper Joshua Hammond, when their convoy was hit by an improvised explosive device (IED) near Lashkar Gah.

In his final despatches to his commanders in London, he wrote: “I have tried to avoid griping about helicopters - we all know we don't have enough.

"We cannot not move people, so this month we have conducted a great deal of administrative movement by road. This increases the IED threat and our exposure to it."

In the documents classified "Nato Secret", Colonel Thorneloe, from Kirtlington, near Oxford, said he had "virtually no" helicopters of the type which would allow him to move troops by air rather than road, and that the system used to manage helicopter movements in Afghanistan was "very clearly not fit for purpose".

The e-mailed memos were leaked by an official to Tory MP Adam Holloway, who publicised them in the hopes they will force "ashamed" defence chiefs into taking action.

Holloway, a former Grenadier Guards officer, told BBC Radio 4’s Today programme: “We have been told consistently that the senior officers say that there are enough helicopters to do the job and yet we now have literally in black and white, in a classified document, his weekly update, the fact that that is not the truth.

“If I was a soldier sat in Helmand now and I knew that we could have more helicopters so that they didn’t have to make these road moves with a daily risk to their lives, I think I would be absolutely heaving.” Mr Holloway said the Ministry of Defence had turned down the offer of more helicopters as recently as September.

“On September 8, the MoD had yet another offer by a private company to provide 25 additional helicopters, 2,500 additional hours per month, with choppers flown by ex-RAF people for £7 million a month.

“That’s just over two-and-a-half times the housing benefit payments paid in my constituency each month.

“And what’s more, the guys in these vehicles could have had them by Christmas.”

Times Recommends

• A vicar’s wife: ‘There is no one to fight for us’
• Every little helps at the supermarket
• Ugg or Fitflop? The battle of the boots