The industry has accused the government of delaying the release of figures for the number of students studying for the construction diploma, claiming officials are hiding the poor take-up of the course.

Joe Johnson, director of training at the Civil Engineering Contractors Association, said he and Nick Gooderson, head of standards and qualifications at ConstructionSkills, were promised the figures by the end of September. But they said the schools department had told them the data will not be released until December.

Johnson believed the move was indicative of poor uptake, and accused the government of waiting for a “bad day on the stock exchange to bury the information”.

More than 3,000 students initially expressed interest in the diploma, but Johnson said he feared the number of “bums on seats” was far lower.

He claimed he knew of at least one north London school that had anticipated 200 students and had received just 37. ConstructionSkills disputed the claims. It said places in some schools had been oversubscribed.

Johnson said it was imperative that the figures were released in order for the industry to prepare for the work experience placements.

The schools department said the information would be released at the end of the year, as originally promised.