Michael Gove is facing legal action from a school after it accused the education secretary of attempting to illegally force the primary to convert to academy status.
Lawyers representing the governing body of Downhills Primary, Haringey, north London, have sent a statement of claim to the Department for Education (DfE). Gove has a fortnight to respond to the claims or risks facing a judicial review into his decision.
Success for the school could stall the government's plans to roll out the academy programme and make schools independent of local councils.
Downhills governor Roger Sahota told the Observer: "We are saying the secretary of state has acted unlawfully by forcing Downhills to become an academy and that action is premature in advance of the next Ofsted inspection.
"It is quite clear that the attainment records are improving and what they are doing is ideologically or politically motivated."
Headteacher Leslie Church told the newspaper: "I am neither for nor against academies. I think it is right for communities to decide what school they have.
"Therefore, if the drive to change all schools to academy status is something the government wishes to pursue, I think that is something that should be put before the electorate as a manifesto.
"Outstanding schools are being encouraged into academy status, schools at the bottom end are being forced to become academies, so that leaves schools in the middle and basically my understanding is the financial viability of local authorities is left in the balance."
A DfE spokeswoman said: "Haringey's primary schools are the worst performing in inner London. This year, results went backwards - dropping below both the national and London average in English and maths.
"Similar local authorities in London, such as Hackney and Tower Hamlets, outperform them. It is vital that improvements are made quickly, which is why we are looking at academy sponsorship to turn around failing schools. We cannot simply stand by and let schools fail their pupils year after year.
"The department will respond to the school's letter in due course."
In a speech last week at a south-east London academy, Gove said most local authorities were being "co-operative and constructive" but he said some were being "obstructive" in their approach.
The education secretary highlighted Haringey Council in his remarks, saying he had been asked "not to challenge" the leadership of the borough's lowest performing schools.
And in his speech he said: "They are more concerned with protecting old ways of working than helping the most disadvantaged children succeed in the future.
"Anyone who cares about social justice must want us to defeat these ideologues and liberate the next generation from a history of failure.
"In one of the most disadvantaged parts of our capital city, poor children have been deprived of the skills they need to succeed."