The need to dismantle the "Berlin Wall" between private and state schools has long been a point of discussion on left and right. In an issue earlier this year, entitled "The 7 per cent problem", the New Statesman explored this subject in depth, publishing a widely-read essay by David and George Kynaston. A leader the following week questioned why, in contrast to Michael Gove, Labour had been largely silent on how it aspired to narrow the divide.

But in a speech tomorrow morning at Walthamstow Academy, shadow education secretary Tristram Hunt will change that. He will vow to end the "corrosive divide" in education by making the £700m currently received by private schools in business rates relief (larger than the amount they receive through their charitable status) conditional on them meeting minimum standards of partnership with the state sector. At present, he will warn: "The only possible answer to whether they earn their £700m subsidy is a resounding and unequivocal 'no'." Too often, the benefits provided by private schools to their communities are limited to entrance to displays and exhibitions or the annual use of sporting facilities.

Under Hunt's plan, they will need to do far more to justify the retention of their subsidy. As part of a new "Schools Partnership Standard", private schols will be required to:

- Provide qualified teachers in specialist subjects to state schools.

- Share expertise to help state school students get into top universities.

- Run joint extra-curricular programmes where the state schools is an equal partner so children can mix and sectors learn from each other.

It's a radical and potentially transformative plan. Labour has pledged to amend the 1988 Local Government Act to make business rate relief conditional on partnership, and to also amend the Education Act and the Independent Schools Regulations to establish the criteria on which private schools will be judged. Non-compliance or failure to demonstrate effective partnership will result in private schools losing their eligibility for business rate relief, incurring a cost that could run into hundreds of thousands of pounds.

Hunt will say: "There can be little doubt that Britain is an increasingly divided country. I want to talk about one of those sources of division within British life. A divide that has become emblematic of a country run for the benefit of the privileged few not the many. The divide between private and state education.