The ex-Liberal Democrat leader is chairing a cross-party commission aimed at addressing inequality in the education system which has been set up by the Social Mobility Foundation think-tank.
Mr Clegg also warned that the planned shake-up of the school funding formula in England would require an injection of cash to compensate the “very considerable losers” who will face a “dramatic change” in the amount they have to spend.
The Social Mobility Foundation published research showing how children’s performance at school depends upon which part of the country they grow up in, with large regional variations across England and Wales.
Mr Clegg said: “It is clear that Britain is a starkly unequal country. It is an indictment of our society that a child born today stands less chance of realising their potential if they are born in a different part of our country to another child.”
The research found that 70 per cent of 16-year-olds in London gained five good GCSEs compared with 63 per cent in Yorkshire with such inequalities persisting - and in some cases worsening - over the past three decades.
Areas such as the North East, Yorkshire and the Humber, the West Midlands and the East Midlands are said to have persistently under-performed, while London’s performance has surged.
Mr Clegg said: “What is now becoming clear is that inequality in education comes in many shapes and sizes. It is not just the relative wealth of parents that holds large numbers of bright kids back: it is postcode inequality too. What part of the country a child grows up in has a real impact on their life chances.”
He suggested that finding a way to attract the best teachers to work in poorly-performing areas could be part of the solution.
“One challenge that has become clear is how to get high-quality teachers into struggling schools in remote or coastal areas. Teach First has had great success bringing talented young teachers into deprived inner-city areas in London, but it is one thing to attract bright people to live in one of the world’s great cities; getting them to move to more remote parts of the country is quite another thing. So we need fresh ideas about how to attract and retain high-quality teachers in these places.”
He added that “pay may well play a role in it” but conceded that it was an “incredibly sensitive issue”.
“It may play a role in trying to get some of the brightest teachers, the best teachers into those schools where they are presently not putting themselves forward for employment.”
He also raised concerns about the planned reforms to the school funding formula, which were announced by Chancellor George Osborne in November’s spending review.
“The aspiration of moving to a national funding formula is a very good one, but the devil - to put it mildly - will be in the detail,” he said. My own view, having looked at it in considerable detail when I was in government, is that introducing a standard formula across the country, of course it will mean that there are some winners but it also will mean there will be some very considerable losers as well.”
“It is pretty difficult to do that without pump-priming the introduction of any new funding formula with considerable amounts of money.”
Mr Clegg, who is joined on the commission by Tory Suella Fernandes and Labour’s Stephen Kinnock, called on MPs from all parties to set aside “tribal differences” to work together on the big challenges facing the UK.
“We are in a particularly volatile period in British politics right now - perhaps the most turbulent and unpredictable since I was at school myself in the 1970s,” he said.
“In these circumstances it is both easy and tempting for parties to retreat to their comfort zones and indulge themselves in tribalism. It is a temptation that we must resist.”
Mr Kinnock echoed that view: “One of the fundamental problems we have with our political system, highly confrontational as it is, is that the problems we are trying to solve transcend the vagaries of the electoral cycle.
“The countries that have successfully reformed and pushed their education systems forward are the ones that have created 10, 15-year plans where you put on a piece of paper what you are going to do, you get it signed off in a way that is not connected to the next electoral cycle.
“That is a huge change in our political culture but in my view some of the big issues which are areas of strategic national interest, like the future of our education system, our NHS, our infrastructure, they do not obey the five-year electoral cycle.”