Ruth Kelly has strongly defended her decision to send her son to a £15,000-a-year private school, insisting that she was acting on the advice of educational experts because he had learning difficulties.

The former Education Secretary said that she had taken the child out of the state sector after receiving "professional advice" that he needed specialist support "as soon as possible". The decision has been criticised by a number of Labour colleagues.

"Like any parent, my first thought was to do the right thing for my child," Ms Kelly said in a statement.

"Acting on professional advice - which the local authority accepts - I am placing my son in a school that will be able to meet his particular needs. He will attend this school for a couple of years before he begins at a state secondary school."

Ms Kelly, who is now the Communities Secretary, said that her other three children would continue to be educated at the same state school that her son had attended. She added that the taxpayer would not be asked to meet the costs.

"It is not uncommon for pupils with substantial learning difficulties to spend some time outside the state sector to help them progress - sometimes this is paid for by the local authority. In my case, I have not and will not seek the help of the local authority in meeting these costs."

"I appreciate that some will disagree with my decision. I understand why, but we all face difficult choices as parents and I, like any mother, want to do the right thing for my son - that has been my sole motivation."

Earlier, Downing Street also defended the decision, saying that Tony Blair "supports absolutely" the right for all parents to send their children wherever they thought best for their education, regardless of their post.

The row began this weekend after it emerged that a minister had withdrawn a child from a state school, choosing instead a preparatory school for children with learning difficulties on the basis that local state provision was not sufficient.

The decision has come under fire from several Labour MPs, with one left-wing MP branding it a betrayal of the party’s principles and "a slap in the face". And Margaret Hodge, Trade and Industry Minister, admitted there was a public interest in whether Labour MPs sent their children to private schools.

But a spokesman for the Prime Minister said that the holding of ministerial office should not be a bar to parents sending their children outside the state system.

"What the Prime Minister supports absolutely is the right of parents to make choices about their children’s education which are best suited to their children’s needs irrespective of who their parents are or what job they do," he said, adding that Mr Blair had always believed in a "mix of provision" in education.

"For some pupils inclusion in the mainstream system will be the answer. For other pupils that will not be the answer."

Mr Blair himself was criticised in 1995 for sending his son, Euan, to the grant-maintained Catholic London Oratory school in Fulham, London, instead of a local comprehensive.

David Cameron also refused to condemn the decision, saying that he did not think it was hypocritical but adding he intended to send his own children to state school.

The Conservative leader told GMTV it was a "personal matter", adding: "Some people are going to say it’s hypocrisy. Well, if they were going to abolish private education then it would be hypocrisy but they’re not.

"People should recognise that politicians like everyone else are parents first and will act in the best interests of their children. I’d like my children to go to a state school, that’s my intention, but you must always do the right thing as a parent."

Alan Johnson, the Education Secretary, refused to comment on the controversy saying there were "privacy issues" involved and he did not know enough about the case to make a statement on it. But he insisted that the Government was trying to ensure the state sector offered the same level of service as the private sector.

Several MPs commented on the decision without knowing who the minister involved was. Ian Gibson, the Labour MP for Norwich North, said: "I think it’s wrong. You should set an example as a minister and support your local school. It is a slap in the face for the teachers and the pupils in the school that the child has been taken out of."

The school in question, where pupils board weekly or termly, is in a country house in the Home Counties. It has 60 pupils aged 7 to 13 and offers extensive grounds, a heated swimming pool, tennis courts, golf and horse-riding. Its main purpose is to help children to prepare for public school entrance exams and in recent years its pupils have gone on to Winchester, Harrow, Rugby and Gordonstoun.

The case has the potential to embarrass the Government by highlighting how a minister who has been involved in education policy is dissatisfied with the special needs provision in her area. The Government has faced criticism for closing special schools while seeking to cater for special needs children in mainstream schools, under a policy of encouraging their schooling within the state system where possible.

The issue of private and selective education has proved a thorny issue for the Labour party. Harriet Harman also infuriated many of her colleagues when she chose to send one of her sons to a selective grammar school, and another to the London Oratory.

And Diane Abbott, who had previously criticised the Prime Minister and Ms Harman for sending their children to selective schools, caused an outcry when she sent her son to a private school, after concluding that the education record of her local secondaries in Hackney was too poor.

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