The SNH offices were relocated from Edinburgh to Inverness

It claimed the costs of relocations had varied significantly and the Scottish Executive has failed to measure the policy effectively.

Trades unions seized on the report and urged an immediate end to the practice.

However, the executive insisted the jobs had been welcomed in areas of Scotland that needed employment.

The relocation policy was introduced by the executive in 1999, with the aim of spreading the benefits of devolution throughout the country.

Scottish Natural Heritage (SNH) was moved from its base in Edinburgh to new headquarters in Inverness at a cost of more than �21m.

It is difficult to determine whether relocations are good value for money Robert Black Auditor general

By May this year, 1,653 public sector jobs had been transferred from Edinburgh, with 933 of those going to Glasgow.

The Audit Scotland report found that, while there was some limited evidence of such moves resulting in efficiency gains, the wider benefits had not been measured.

Robert Black, the auditor general for Scotland, said: "The executive has plans to evaluate the impact of the policy, but little had been done to date.

"For that reason it is difficult to determine whether relocations are good value for money.

"I would encourage the Scottish Executive to define more clearly the measures of success that it is applying to its relocation policy and to develop its plans for evaluating the benefits of relocation."

Issues raised

The report recommended that the executive set out measures of success to help monitor the benefits of future moves and guidance on the criteria for deciding whether a relocation should go ahead.

It also said there should be clear reasons behind the choice of a location.

The Public and Commercial Services Union (PCS) has called for a halt to the policy in a letter to First Minister Jack McConnell.

It said the report confirmed many of the issues it had been raising for seven years.

It's important to take these jobs to wider areas of Scotland, particularly those with more fragile economies Scottish Executive spokesman

Scottish secretary Eddie Reilly said: "Our union is not prepared to continue to give any industrial co-operation with the policy of relocation unless it is founded on sound principles and is not carried forward on the basis of compulsory redundancies or compulsory relocation of staff."

Scottish National Party finance spokesman John Swinney said: "This report shows in a number of cases relocation has not saved money but incurred more costs for the Scottish taxpayer."

An executive spokesman defended the policy but said ministers would reflect on the report.

He said: "The executive has had a commitment to relocate public sector jobs around Scotland and we have delivered on that commitment.