The headmaster of Eton College has hit back at Labour’s plans to abolish private schools, saying they make no financial sense and will not benefit children left behind by the education system.

In an interview with the Guardian, Simon Henderson, who became head of the world-famous private school four years ago, acknowledged the public mood had shifted and a battle lay ahead for the future of private education.

He said Eton, which was founded in 1440 by King Henry VI, would make its case for survival as a “positive force for good” in the education system. Asked if he thought the elite boarding school, which charges annual fees of more than £40,000, was facing an existential threat, he responded: “I hope not.”

Henderson was speaking after delegates at the Labour party conference voted in favour of a radical set of policies that would abolish private schools by removing their charitable status and redistributing their endowments, investments and properties to the state sector. Labour also wants to limit the number of privately educated students at university.

The Eton head agreed there was inequality in the education system and supported Labour’s ambitions to improve the lives of children across the country, but said “abolishing excellence” was not to the way to achieve those aims.

“I don’t think that by abolishing some of the best schools in the world, by confiscating and redistributing their assets, that we are going to improve the life chances of young people who have been left behind by the education system.” He advocated, instead, increased partnership between private and state schools.

Henderson said independent schools saved the state school system, and therefore taxpayers, £3.5bn a year. He said they contribute £13.7bn to the economy, generate £4.1bn in annual tax revenues and support about 303,000 jobs.

“More fundamentally than that, I don’t think it will work,” he continued. “I don’t think it will improve equality within the education system.”

Henderson said Eton had changed significantly from the school that produced the likes of current prime minister Boris Johnson, former prime minister David Cameron and the leader of the House of Commons, Jacob Rees-Mogg.

“What you are talking about there is a very small number of individuals who left the school over 30 years ago and who have made it to the top levels of politics. Eton in 2019 is a much more inclusive and diverse population than it was previously.

“My responsibility as headmaster of Eton in 2019 is to look at what Eton is doing now and in the future. I can’t change what it may or may or may not have done in the past.” He agreed, however, that the image of Rees-Mogg lounging on the frontbenches during an emergency debate on Brexit was “not a good look”.

Facebook Twitter Pinterest Boris Johnson when a pupil at Eton College in 1979. Photograph: Ian Sumner/Rex/Shutterstock

Johnson, meanwhile, condemned the Labour plan as “a measure from the 1970s”, while conceding that his own private education was likely to have helped his ascent to Downing Street. Speaking to reporters on his way to the UN general assembly in New York, the prime minister said the idea showed “unbelievable hypocrisy”.

“It’s extraordinary they have excavated this from the crypt of what I thought had been long-buried socialist ideology,” Johnson said. “Let’s be clear, this would cost £7bn of taxpayers’ money to educate at public expense all the pupils who would not longer be educated privately, as Jeremy Corbyn was, and indeed the offspring of several Labour ministers I will not name.”

Asked if it was unlikely he would have become prime minister if he had not been privately educated, Johnson did not discount this: “I have been very fortunate in my life in all sorts of ways. I certainly owe a lot to my education. I certainly would agree strongly with that.”

Henderson insisted Eton was playing its part in supporting state schools and sponsoring deserving students from non-wealthy backgrounds, offering scholarships and bursaries which ensure that currently more than 90 boys out of 1,300 at the school pay no fees at all.

Steven Longden, a state school teacher and coordinator of the Labour Against Private Schools campaign group, said: “Obviously the private schools are not going to give up their very privileged position without a fight. We just don’t trust that private schools are going to become more socially just institutions if left to their own devices.”

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The Independent Schools Council, which represents 1,350 private schools in the UK including Eton, has warned that any move to abolish private schools would be in breach of the European convention on human rights on the right to choose education.

However, Leon Glenister, a specialist barrister in education law, said: “The right to education under the European convention on human rights has mostly been invoked where children are substantially deprived of any education, for example in relation to school exclusions or cases involving a disability.

“Labour’s proposals raise a different, less explored, question on the extent to which the right to education encompasses a right to choose a particular type of education. It is a question the courts have not particularly grappled with, and it is not as clear-cut as some are suggesting.”

An alternative route, he said, might be for private schools to challenge any attempt to redistribute buildings and facilities. “The convention also protects the right to property, which is regularly invoked in expropriation cases. That is perhaps the more obvious potential breach of convention rights.”