Chris Keates, general secretary of the NASUWT teaching union, has said that Michael Gove has embarked on a "cynical and wholly unjustifiable" attempt to discredit GCSEs.
She added that today's proposals to replace GCSEs with an English Baccalaureate Certificate were "entirely driven by political ideology rather than a genuine desire on the part of the coalition Government to reform the examination system in the best interests of children and young people".
A further deep concern is the plight of those young people set to take GCSEs in the next two years.
They have now been told publicly that the exams for which they are working on are discredited and worthless.
The actions of the Secretary of State in this regard are unacceptable and the lack of concern for the impact and motivation of young people and teachers working towards GCSEs is disgraceful.
The GCSE exam for children in England is to be replaced by an English Baccalaureate Certificate with the first courses to begin in 2015.
Education Secretary Michael Gove is to unveil details of a major overhaul of GCSE exams marking a return in part to the old O-level system.