Jeremy Corbyn
Jeremy Corbyn has been received warmly by the NUTGetty Images

The "forced academisation of all schools" proposed by the education secretary Nicky Morgan is "an ideological attack on teachers and on local and parental accountability", Jeremy Corbyn has told the National Union of Teachers.

Corbyn is the first party leader to address the main teachers' union's annual conference in 40 years, and his speech was rapturously received. He told teachers that ministers were attempting to "shut parents out of a say in how their children's schools are run", in a speech which blasted Tory plans to convert every school in the country into an academy.

"The Tories want to shut parents out of a say in how their children's schools are run," he said, to thunderous applause. "I want schools accountable to their parents and their communities – not to those pushing to be first in line for the asset stripping of our education system."

He went on to describe Morgan's plans, which would overhaul the way schools are run in Britain, as "asset-stripping", saying: "I want schools accountable to their parents and their communities – not to those pushing to be first in line for the asset-stripping of our education system."

Christine Blower, the general secretary of the NUT, welcomed the Labour leader's speech, saying "we've waited a long time for a politician who says things that chime with the NUT".

"The approach of the Labour leadership now is to talk to people and have engagement about their policies," Blower told Schoolsweek. "Jeremy got in touch with us and asked if he could come and speak to delegates."

Corbyn spoke of his lifelong commitment to the union movement, and with the NUT likely to debate a motion on industrial action over the government's controversial academies plan, his words seem set to strengthen teachers' resolve.

The rebellion against the government's academy plans has grown this week, with some Tory councils, including the one which covers David Cameron's Witney constituency, speaking out over the proposals.

"I feel really angry," said Melinda Tilley, a Tory councillor for 18 years and acabinet member for education for Oxfordshire county council. "If it's not broke don't fix it. I don't think schools should be forced. We've been supportive of the government's agenda. We were going along quite well, helping schools to convert where we could. Now all of a sudden they are going to force the rest of them. It makes my blood boil. I'm put in a position where I can't protect schools. One size does not fit all."

Academies are state-funded schools which are run directly by the Department for Education rather than by local authorities as self-governing non-profit trusts, and which are not obliged to follow the National Curriculum. Critics worry that they represent a back door to privatisation of education, and that they are not subject to the same level of scrutiny as schools run by local authorities. Teachers' groups worry that the system gives private entrepreneurs the chance both to profit from running a school and to use unqualified teachers promote fringe ideas like creationism.