By Sanjoy Majumder BBC News Online correspondent in Delhi

India's influential and hungry press corps got a glimpse of the man heading for the presidency of the world's largest democracy - and were lost for words.

APJ Abdul Kalam, a scientist who helped turn India into a nuclear power, admonished, lectured and recited poetry to a gathering of bemused journalists in the Indian capital, Delhi.

Kalam is seen as the prime mover of India's nuclear programme

Dressed in casual shirt and trousers, Mr Kalam evaded politically loaded questions, such as his views on religious violence in Gujarat, preferring to read out prepared answers.

But he strongly defended India's nuclear programme, arguing that it had prevented hostilities between India and Pakistan from breaking out into an all-out war.

Finger-wagging lecture

Few journalists who regularly cover Delhi's political circuit could have been prepared for Wednesday's news conference.

Mr Kalam distributed copies of his "Song of Youth" - described as his vision of India's future.

Beaming from ear to ear, he said that by putting him forward for president, the government had shown "technology is going to be used for development of the nation".

Nuclear deterrence on both sides helped [India and Pakistan] not to engage in a big war

Abdul Kalam

The scientist's most recent role has been that of college professor - something that was very evident in his approach to the media.

He gently chided persistent questioners, emphasised his key arguments by repeating them slowly for his listeners and, when in doubt, turned to his trusty notes.

Mr Kalam, who is Muslim, was also pushed hard to respond to the recent Hindu-Muslim violence in Gujarat which has led to nearly 1,000 deaths.

But he refused to be drawn into a direct reply, saying instead that "what has happened in Gujarat is very painful".

The answer to such violence, he said, was for religion to "graduate" into spiritualism, and for political leaders to become more compassionate.

Nuclear deterrence

Mr Kalam also strongly defended India's nuclear programme and ambitious missile defence plans.

Professor Kalam's career was in defence research

"Nuclear deterrence on both sides helped [India and Pakistan] not to engage in a big war [and] avoid a nuclear exchange," he said.

In doing so, he echoed remarks by Pakistan's President Pervez Musharraf and unwittingly pitched himself in opposition to India's own position - which runs counter to that.

The politically correct Abdul Kalam is seen as a shoo-in for the presidency, with the only challenge coming in the form of an 87-year-old feminist and freedom fighter who is the candidate put up by India's communist parties.

Sartorially challenged?

But many in India believe Mr Kalam will bring a refreshing change to the largely ceremonial presidency, not least because of his disregard for formal wear and his unruly silver hair.

Mr Kalam's rock-star like hair has been the subject of much media scrutiny with a report in the Indian Express daily suggesting that it had been designed by one of Delh's top hair-stylists.

At his press conference, the nuclear scientist suggested that he would do little to change the way he looked or dressed, despite the trappings of presidential glamour.

Nevertheless, the Indian Express commissioned some of India's leading fashion designers to suggest ways in which Mr Kalam could improve his wardrobe.

Leading fashion gurus debated suit lengths and footwear, but were unanimous on one point - India's likely next president is the epitome of simplicity in style.