Schools standards will only improve once the quality of teaching in classrooms is raised, shadow education secretary Tristram Hunt has said.
Michael Gove earlier put forward proposals to shake-up the education system which he hopes will end the "Berlin Wall" divide between state and private school sectors.
"Improving school standards starts with a qualified teacher in every classroom. Until Michael Gove commits to this, he is ruling himself out of any serious debate about how we raise standards in our schools," Mr Hunt, said.
"Whether on discipline, delivering extra-curricular activities or on improving learning outcomes, it all hinges on the quality of the teacher in the classroom.
"Raising the quality of teaching - that is where the focus needs to be and that is what Labour is concerned with. The Tories have lost sight of this and are undermining school standards as a result."
The shadow education secretary Tristram Hunt has refused to rule out sending his children to private school in the future.
Mr Hunt, who was promoted to the role during Ed Miliband's last reshuffle, insisted he had "absolute faith" in the state sector, but said you "can never say never" about what might happen in the future.
Speaking on The Agenda, the MP said:"I'm first and foremost a parent and a father, and I'm not saying that there are no circumstances ever in the future in which that decision might not have to be taken.
"But my kids are in the state sector, they're going to continue there, but I think it's important for politicians to be honest, and were something to occur in the future which necessitated that situation, I don't want people to say 'well he said he'd never do it'.
"I think you have to be open and frank about those potentialities as a parent."
The Agenda with Tom Bradby will be broadcast on ITV tonight at 10.35pm
Shadow education secretary Tristram Hunt described the case at King's Science Academy as the latest "deeply concerning" episode in a "string of failings" in the Government's Free School programme.
"Labour has long warned of the dangers that a lack of financial oversight and allowing unqualified teachers to teach in our classrooms on a permanent basis would cause," he said.
"The case of KSA Free School further exposes David Cameron's weakness on school standards. It proves yet again that it is not possible for thousands of schools to be run directly from Whitehall and is further proof that this out-of-touch Government has no plan to deliver for all children."