A major strategy document published this summer said good science and maths teachers should be paid more and the School Teachers' Review Body, which makes pay recommendations to ministers, is considering how to do this.
Education Secretary Charles Clarke has already told the review body that inflation-only rises are "essential". Such increases are likely to be pegged at 2.5 per cent - effectively frozen in real terms. And the DfES has said there is no need for a specific science salary scale.
"Schools already have flexibility to pay more to science teachers if they wish to or they have recruitment and retention difficulties," a spokesman said. "It is better for schools to make their own decisions about targeting pay than for us to do so for them. In some schools the issues are about modern foreign languages or English teachers."
The Government made strong statements on science teachers' pay following the comprehensive spending review. A joint strategy paper from the Treasury, DfES and the Department for Trade and Industry said: "The Government is determined to enhance pupils' science, mathematics and technology education by improving prospects for the recruitment and retention of science and mathematics teachers, including through paying more to good science and mathematics teachers."
Science lobbying groups question if enough is being done to solve the teacher shortage. Peter Cotgreave of Save British Science said: "One wonders whether the issue is not flexibility, but rather the total money available."
The Institute of Physics said differential pay was needed to end the crisis in the subject. Teacher support manager Chris Shepherd said the institute was aware that the policy might be divisive, but "the severe shortage in physics recruitment requires urgent measures".
Science teacher shortages were highlighted last year in an influential report by Sir Gareth Roberts, president of the Science Council, which said they should be paid more. The STRB is due to report at the end of January.