Compulsory redundancies in the military, compared to voluntary redundancies for civilians in the Minsitry of Defence, have been labelled "grotesque" by an influential commons committee.

In a scathing report, the Commons defence committee questioned whether the terms on offer were "fair or appropriate" and dismissed Ministry of Defence explanations of the "shocking" difference.

Insufficient attention had been given to retraining soldiers, sailors and airmen for roles the military faced shortages in, it suggested.

Around two in five of 2,860 servicemen and women laid off late last year in the first phase of a huge reduction in manning levels were made compulsorily redundant.

In contrast, the first two tranches of redundancies in civilian staff - set to total 15,000 over several years - were all done on a voluntary basis, the committee heard.

The MoD's senior civil servant, permanent secretary Ursula Brennan, said that was partly because civil servants were more "flexible" while the armed forces tended to have "specific trades".

Defence minister Andrew Robathan pointed out in the Commons that the armed forces had been "less forthcoming" with applications for voluntary redundancy than civilian staff.

Both were condemned by the committee as inadequate explanations.

"The argument that civilians are flexibly employable whereas the military are not runs contrary to our experience of the breadth of the military training we have witnessed on operations," it said

"The MoD should set out what opportunities and encouragement it gives to those in the armed forces who face compulsory redundancy to retrain, especially into 'pinch point' trades."

Brennan's argument also implied "a lack of strategic vision as to the direction to be taken by the civilian component of the MoD", the MPs said.

"On the other hand the minister's assertion, that many civil servants but insufficient members of the armed forces have applied for redundancy, ignores the question of why that should be so.

"The MoD should consider whether the terms of redundancy offered to either the military or civilian staff are fair or appropriate in the light of the stark and shocking difference between the application of compulsion in redundancy to the two branches of service in the MoD.

"For military redundancies to be compulsory in 40% of cases, yet for civilian redundancies to be compulsory in none, is so grotesque that it requires an exceptionally persuasive reason.

"We are not persuaded by either of the two reasons we have been given."

The Tory MP who chairs the committee, James Arbuthnot, said "Why cannot the MoD retrain service personnel, who face redundancy, to fill those many trades where there are shortages, such as combat medical technicians or intelligence gatherers?"

A second tranche of military redundancies were announced this month under the Strategic Defence and Security Review (SDSR) intended to help plug the £38 billion black hole in the defence budget.

Up to 2,900 members of the Army, 1,000 members of the Royal Air Force and 300 members of the Royal Navy, including military top brass, were told they were losing their jobs.

The committee also accused the MoD of impeding its job of scrutinising spending by "hiding behind security classifications" and declining to make secret documents available to MPs.

Defence Secretary Philip Hammond said: "The select committee's report is simply wrong in what it says on military redundancies.

"Every opportunity is being given for military personnel to retrain either for alternative roles in the Armed Forces or in civilian life, but the simple fact is we have to tackle the massive deficit we inherited from Labour and the huge black hole in the defence budget.

"We have already announced the reduction in military and civilian manpower that we will have to make to get our Armed Forces on a stable basis for the future.

"Criticism from Labour rings equally hollow - they are the cause of the problems we are now resolving.

"I am determined to get the defence budget back into balance so our Armed Forces have certainty and clarity about the future."

The Ministry of Defence also insisted the overall civilian headcount reduction would be 25,000 by 2015.

Shadow defence secretary Jim Murphy said: "There is a thin line between callousness and carelessness and Ministers need to start taking responsibility for their decisions.

"Thousands of service personnel are being unceremoniously sacked. It is essential that the painful impact of David Cameron's decisions is minimised wherever possible. The Committee are right to suggest prioritising retraining for all those made compulsorily redundant. The transition between military and civilian life is always difficult and the Government should do more to provide opportunity and stability."