Sai Baba’s activities are being studied by the Foreign Office which is considering issuing an unprecedented warning against the guru to travellers.

The Times has learnt that three Britons have apparently taken their lives after placing hope in India’s most popular holy man.

One of them had complained of being repeatedly sexually molested by Sai Baba at his ashram in Puttaparthi near Bangalore.

Michael Pender, an HIV-positive student, was found dead at a London hostel after taking alcohol and painkillers. He had already tried to commit suicide at the holy man’s headquarters.

Aran Edwards hanged himself at home in Cardiff after joining a Sai Baba support group and being encouraged to write to the guru to solve his psychological problems.

Mr Edwards sent a flurry of anxious letters but was devastated after receiving no replies and being told that the guru did not read his mail.

Andrew Richardson, a South Africa-born British national, jumped off a building in India shortly after visiting Sai Baba’s ashram.

Among visitors who have paid respects to Sai Baba are the Duchess of York, the Prince of Wales’s architect Keith Critchlow, the cricketer Sachin Tendulkar and the Indian Prime Minister Atal Behari Vajpayee.

Sai Baba’s message is being preached in more than 500 British schools through charities which claim to provide non-denominational education in “human values”.

Tom Sackville, a former Home Office Minister, last night urged the Government to take decisive action to warn teachers and pilgrims of the dangers of becoming involved with Sai Baba. The guru’s reputation is plummeting after the United Nations cancelled a conference at his headquarters, issuing a condemnation of his alleged sex abuse of youths and boys.

Unicef pulled out of a conference it was due to sponsor with the guru’s educational organisation in Puttaparthi last September.

The UN’s cultural agency issued a trenchant statement: “The organisation is deeply concerned about widely reported allegations of sexual abuse involving youths and children that have been levelled at the leader of the movement in question, Sathya Sai Baba.

“Whilst it is not for Unesco to pronounce itself in this regard, the organisation restates its firm moral and practical commitment to combating the sexual exploitation of children, in application of the UN Convention on the Rights of the Child, which requires states to protect children from all forms of sexual exploitation and violence.”

In hundreds of British schools, Sai Baba-influenced educational programmes on “human values” are currently being promoted as part of the National Curriculum.

The Charity Commission met the trustees of one of the educational charities involved, the Sathya Sai Education in Human Values Trust UK, last year and “found no concerns”, a spokesman said.

Mr Sackville, chairman of the anti-cult organisation Fair (Family Action Information and Resource), said that he had successfully intervened to persuade a girls’ school to reject a Sai Baba-inspired course.

“Schools are not on their guard because at official level they are not given any steer,” Mr Sackville said. “Some other countries would have had official warnings.”

He said that Whitehall was strongly opposed to letting the British Government apply sanctions to cults, which civil servants describe respectfully as “new religious movements”.

As for the Charity Commission’s clean bill of health to the Sai Baba educational organisation, Mr Sackville said: “There’s a lot of very naive people around in these government institutions.”

He called on the Foreign Office to issue a warning against Sai Baba along the lines of recommendations to travellers to beware the dangers of Aids and violence abroad. The Foreign Office is believed to be considering putting out just such advice.