Britain's frontline forces are facing a manning shortfall which exceeds the total number of troops deployed to Afghanistan, an influential House of Commons watchdog body warned today.

The Public Accounts Committee said the armed services were currently 5850 men and women short of full strength, and that the damage of repeated tours of duty to family life had reached crisis point for many.

There are 5700 service personnel in Afghanistan, where they endure daily attacks from Taliban insurgents. Two were killed at the weekend, bringing the number who have died there since 2001 to 63.

The committee's report on recruitment and retention said bluntly that there were too few soldiers, sailors and airmen to meet the demands of simultaneous wars in Iraq and Afghanistan.

Frequent overseas deployments, heavier workloads and the problem of balancing service and family life were among the main reasons for a leaving rate which had hit a 10-year peak.

Edward Leigh, the committee chairman, said: "The Ministry of Defence has been relying for too long on the goodwill and courageous spirit of our servicemen and women to compensate for increasing shortages in all three services.

"The staffing situation has reached the point where there are simply not enough trained people to meet levels of military activity planned years ago - let alone the heightened demands now being placed on them by commitments such as operations in Iraq and Afghanistan."

The report said the overall shortfall equated to 3.2% of full strength and was 700 personnel worse than the same time last year - the equivalent of losing an entire battalion.

It warned: "The impact of continuous downsizing, pressures and overstretch is affecting the department's ability to retain and provide a satisfactory life for armed forces personnel."

Several key factors such as workload, inability to plan for life outside work and the impact on family life, "have not been addressed".

Mr Leigh added: "The MoD has no long-term strategy to deal with the outflow, especially among highly-qualified specialist personnel.

"The MoD must think hard when it makes cuts in recruitment about the consequences for manning levels some years along the line.

"The consequences to manning levels are almost impossible to rectify speedily and any measures taken seem to cost more than was saved by the original cuts.

"The MoD does not consider our forces with their current numbers of service personnel to be overstretched'. Let us fervently hope that it will not take some future operational failure on the battlefield for the department to change its mind."

Derek Twigg, the Defence Minister, conceded that the high tempo of operations was putting pressure on the personnel involved, but insisted that the forces could cope.

He said: "The Chief of the Defence Staff himself has said that said that the forces are very stretched, but can sustain what they are already doing.

"With the drawdown of troops in Bosnia and Northern Ireland, and the reductions already made in Iraq, some of the pressure should start to ease.

"I accept that we have manning challenges in some areas, but we are taking action."

Roger Bacon, Conservative MP for South Norfolk, said: "Our troops are doing a superb job and it is a sign of failure that the MoD cannot hang on to them.

"The MoD must provide stability and certainty for them and their families or it will continue to lose experience, manpower and money."