The report said widespread impact on learning was not achieved

The HM Inspectors study said the main elements of the 2001 deal on pay and conditions had been implemented, but it questioned the impact on pupils.

The �2bn deal included a 23% pay rise for teachers and more support staff.

Education Minister Hugh Henry said the reforms had brought in an "era of unprecedented stability" to classrooms.

The flagship deal was struck between the Scottish Executive, local councils, and teacher organisations, following the McCrone report in 2000 on teachers' pay and conditions.

The inspectors' report, published on Tuesday, found that reduced class contact time, new career structures, better professional development and new management structures were all being established in schools.

While we found specific examples of good practice, widespread impact on children's learning remains to be fully achieved Graham Donaldson Senior chief inspector of education

It also said the range and quality of support staff had improved, and classroom assistants were playing an increasingly positive role.

The senior chief inspector of education, Graham Donaldson, said: "We should not underestimate the scale of the work that has been carried out.

"As yet, however, the agreement has largely affected teachers' pay and conditions, professional development and career structures.

"While we found specific examples of good practice, widespread impact on children's learning remains to be fully achieved."

McCrone review

Education Minister Hugh Henry insisted that pupils were benefiting from a stable and well-rewarded workforce as a result of the deal.

He said: "Schools no longer deal with the threat of strikes, and our pupils do not suffer the disruptions of previous generations.

However, he added that he would review the deal to ensure it was delivering all it could for pupils.

The SNP's education spokeswoman Fiona Hyslop said the executive had "clearly failed to implement McCrone effectively".

She said the report called for urgent local reviews of its operation which "must be followed through".

The report concludes that there is little evidence the Teacher's Agreement has been a success James Douglas-Hamilton Scottish Conservatives

"The report also shows that there are concerns over teacher numbers which must be maintained and new teachers will need to be recruited to ensure adequate cover, particularly if we are to have meaningful cuts in class sizes," Ms Hyslop said.

Scottish Conservative education spokesman James Douglas-Hamilton said: "The report concludes that there is little evidence the teacher's agreement has been a success.

"This is mainly because the executive doesn't know if it is working or not. Considering the initiative cost more than �2bn of public money, this isn't good enough."

He added that the Chartered Teachers scheme, a cornerstone of McCrone agreement, had been "ineptly devised and implemented".

Local government body Cosla said the reforms had led to major improvements in industrial relations.