The West Midlands slipped further behind the south of England despite record A-level results which saw more pupils than ever before achieving “A” grades.

Across the West Midlands, 23.4 per cent of A-levels resulted in a grade A pass - up by 4.5 per cent compared with 2002. But grades rose fastest in regions where standards were already highest.

The East of England, the South West, London and the South East regions all recorded even higher increases in the number of A grades, despite having better results to start with. In the south east, 29.1 per cent of entries were awadred A grades, up by 6.1 per cent.

Teachers and employers also expressed concern about the introduction in September of Diplomas, the new national qualification which provides an alternative to both GCSEs and A-levels.

And headteachers in the city urged the Government to stop claiming Diplomas were the equivalent of A-levels, and admit they were very different courses.

The diploma system is designed to encourage young people to stay in education by providing them with courses lasting until they are 18 or older, rather than stopping at 16 and forcing them to choose whether to continue. It will also allow employers to have a direct role in helping to shape the curriculum.

Youngsters can follow a Foundation Diploma, equivalent to five GCSEs at the grades D to G, a Higher Diploma, equivalent to seven GCSEs at grade A* to C, or an Advanced Diploma, equivalent to three and a half A-levels.

But Ministers have shied away from the original proposals, drawn up by former Chief Inspector of Schools Sir Mike Tomlinson, to replace A-levels and GCSEs entirely.

Instead, the two systems will run in parallel until at least 2013. The Department for Children, Schools and Families says pupils will be invited to choose the course they wish to follow, although it is unclear how many schools will have the resources to offer both options.

The Government then plans to review secondary education once again, and will decide whether one of the qualifications should be abolished.

Conservatives have accused the Government of undermining A-levels because they are considered “stuffy and elitist” by Labour.

Birmingham Chamber of Commerce said it was concerned at reports that only 20,000 students across the country were due to study diplomas in September.

Kiran Virk, a policy adviser with the chamber, said: “They will combine GCSEs and A-levels and provide students with a mix of academic learning as well as real work-based learning and experience.

“But at the moment, there seems to be a mismatch between the demand and supply elements involved in delivering the courses. The anticipated number of pupils taking up the Diploma qualification has failed to materialise.”

Sarah Evans, head at King Edward VI High School for Girls in Edgbaston, said: “I think there’s a real need for high quality qualifications for vocational areas.

“However what I do worry about is this constant desire to say that these are ‘equivalent’ to A levels, which I don’t think is terribly helpful because they’re different types of assessment, they’re not remotely the same.

“These diplomas should be able to stand – and recognised – on their own merits, not on a comparison.”

Sir Mike, the architect of the new system, said it would help tackle the problem of students being taught only how to pass an exam rather than develop their own knowledge.

Across the country the A-level pass rate soared above 97 per cent for the first time, and the proportion of A grades awarded was 25.9 per cent.

Schools minister Jim Knight dismissed any suggestion that another set of record results showed A-levels were being dumbed down.