Former Education secretary spearheaded citizenship teaching in schools

He is calling on the Schools Secretary Ed Balls to employ a full-time minister to ensure government targets are met.

The Department for Schools insists it is "fully committed to high quality teaching of the subject".

From 2002, citizenship lessons became a legal requirement for pupils from age 11 to 16 at schools in England.

Statutory citizenship education is not part of the national curriculum in Scotland, Wales or Northern Ireland.

Annually, the department for schools has 600 training places available for those already qualified as teachers; a further 200 receive specialist guidance as part of their teacher training.

But Mr Blunkett told the BBC, "when there are 3,500 secondary schools ... we are going to have a real problem," he said.

A year ago, the government announced it would make "understanding core British values" a compulsory part of every child's education.

Mr Blunkett told BBC Radio 4's Today programme: "I think the problem - bearing in mind we have had five secretaries of state for education in as many years - is that we need someone who really does care about implementing a new curriculum subject area."

He added: "This is a new subject area, difficult to bring alive to pupils so that they are active citizens, not just learning by rote in the classroom.