More than 1,500 staff at the Ministry of Defence are waiting to be moved because they are no longer needed by the department, figures have revealed.

Defence secretary Bob Ainsworth said staff that were surplus to requirements - or about to become so - had been placed in the "redeployment pool" and given priority for new jobs.

At the start of the year there were 1,525 employees in the pool, he said, including around 75 who had been on the list for more than two years.

Surplus workers waited an average of six months before finding new jobs, he added.

Last year it emerged there were almost 600 civil servants in similar schemes at the Home Office and Ministry of Justice, leading to opposition claims that they were being paid to do nothing.

In a written Commons answer to shadow chief treasury secretary Philip Hammond, Ainsworth said: "My department manages its surplus staff by using a redeployment pool (RDP). This service enables those who are or who will become surplus to be given priority consideration for vacancies.

"Staff in the RDP usually continue working in their last directorate or are deployed to cover short-term tasks.

"As at January 1 2010 there were 1,525 employees in the RDP, 85 per cent have been in the RDP for less than six months and only five per cent have been there for more than two years.

"On average, staff spend six months in the RDP before finding a post or leaving the

Shadow defence secretary Liam Fox said frontline armed forces would be “perplexed” at the news, adding: "It's becoming ever clearer that the MoD needs a root and branch clear out."

Liberal Democrat spokesman Nick Harvey said: "These figures raise serious questions about the ability of the MoD to manage its civilian staff.

"The Liberal Democrats would cut back on the MoD's bloated bureaucracy and give poorly paid troops the pay they deserve."

The figures  came as Ainsworth prepared to publish a defence green paper to lay out the “tough choices” on spending that the department will have to take.

Today's document is the result of analysis of the changing strategic context, lessons from operations in Iraq and Afghanistan, technological advances and the use of "soft power".

It also examines ways of improving equipment procurement following a review which found the current programme was £35bn over budget with projects running, on average, five years late.

The MoD said it would inform debate, within and outside the military, "about how best to structure defence for the threats, risks and challenges we face now and in the future".