Education Secretary Nicky Morgan has said there is "no reverse gear" on the government's plan to turn all schools in England into academies by 2020.
Speaking to teachers at the annual NASUWT conference in Birmingham, Ms Morgan said the proposal would "not be pulled back" while insisting that the move would empower teachers and enhance standards all over the country.
She added that ideas outlined in the government's 'Education Excellence Everywhere White Paper' would improve the teaching profession by focusing on initial training as well as continuous education.
However Ms Morgan was jeered when she appeared to chastise teachers for "talking down their own profession".
She admitted that the recruitment of teachers was "a challenge" but complained that press releases from the unions seem to highlight the negative aspects of teaching rather than its "rewarding" elements.
During the Q&A session after Ms Morgan's speech, NASUWT general secretary, Chris Keates, urged her to abandon imposing the academies system on the remaining local authority-controlled schools in England.
She said: "Once again Nicky, the Chancellor's announcements are unravelling.
"Don't allow yourself to become the next IDS (Iain Duncan Smith), listen to the concerns being raised.
"If you want education excellence everywhere, than recognise there are outstanding academies, outstanding community schools, outstanding foundation schools, outstanding voluntary-aided schools which prove academies do not have the monopoly on excellence."