´óÏó´«Ã½

Government defence cuts are happening so quickly that they are putting important military skills at risk, the Whitehall spending watchdog has warned.

The Ministry of Defence has to lay off 54,000 staff by 2015, in an effort to reduce expenditure by £4.1bn.

The National Audit Office (NAO) said "profound changes" to working practices would be needed for current performance quality to be maintained.

The government said it was "actively managing" risks to services.

The Ministry of Defence is in the process of cutting 25,000 armed forces personnel and 29,000 civilian staff by 2015, in the biggest round of cuts to the military since the end of the Cold War.

The reductions, set out in the Government's 2010 Strategic Defence and Security Review, are intended to helping close the £38bn "black hole" in the defence budget.

The National Audit Office the department had "little choice other than to make cost cuts early" but, as a result, it had had to begin reducing numbers before it had worked out how this would affect performance.

The NAO said: "The MoD will need to make profound changes to how it works in order to continue with its current level of activity with fewer staff.

"But the NAO has not, so far, seen enough detail to determine whether the department is making sufficiently substantial changes to how it works.

"Without real changes to ways of working, cutting headcount is likely to result in the department's doing less with fewer people or, alternatively, trying to do the same with greater risk."

The head of the NAO, Amyas Morse, said the MoD needed to adopt a "more targeted approach" to implementing the cuts, adding: "The department has acted decisively, but runs the risk that it will lose skills that it needs, worsening the current skills shortage."

For Labour, shadow defence secretary Jim Murphy warned the drive for redundancies was "rushed and wrongheaded".

He added: "Real savings have to be made, including from personnel reductions in the military and civilian workforce, but they must fit within a clear plan of how the MoD will do more with less at home and overseas."

Defence Secretary Philip Hammond said: "Of course, the scale of the financial black hole in MoD's budget that the coalition has inherited meant action was needed urgently. We recognise the risks the NAO identifies and are actively managing them.

"MoD civilians contribute to every aspect of defence in the UK, internationally and in theatre, and these necessary changes will be achieved mostly through reductions in recruiting and by not replacing those who leave."

On Thursday, the House of Commons Defence Committee warned that ministers faced "difficult decisions" on how to spread military resources if they wanted to launch another mission on the same scale as last year's operation in Libya.

But the government insisted it was still able to "project" British power abroad.