NEW DELHI (Reuters) - Indian prime ministerial frontrunner Narendra Modi ruled out the first use of nuclear weapons on Wednesday, seeking to calm concerns after his Hindu nationalist party vowed to revise arms strategy if elected.

Hindu nationalist Narendra Modi (C), the prime ministerial candidate for India's main opposition Bharatiya Janata Party (BJP) and Gujarat's chief minister, waves to his supporters during a public meeting at Krishnagiri in the southern Indian state of Tamil Nadu April 16, 2014. REUTERS/Babu

Modi told the ANI television service the nuclear arms were defensive weapons. India and its rival neighbor Pakistan are both nuclear powers that have been building up their nuclear arms stockpiles and testing long range missiles.

In the 70-minute interview, conducted in the Gujarati state capital Gandhinagar, Modi predicted a record result for his Bharatiya Janata Party (BJP) and said the ruling Congress party would crash to its worst-ever electoral showing.

He also accused journalists of attempting to smear him over sectarian rioting in his home state in 2002 in which more than 1,000 people, mostly Muslims, were killed.

Modi said Indian’s nuclear arms arsenal “is necessary to be powerful - not to suppress anyone, but for our own protection.”

Striking a statesmanlike tone, he upheld a doctrine defined by former Bharatiya Janata Party (BJP) prime minister Atal Bihari Vajpayee, who declared a policy of no first use of atomic weapons after testing several bombs in 1998.

“No first use was a great initiative of Atal Bihari Vajpayee - there is no compromise on that. We are very clear. No first use is a reflection of our cultural inheritance,” Modi said.

NUCLEAR POLICY

Modi’s comments came a week after the BJP unveiled its manifesto, pledging to review India’s nuclear stance, whose two main pillars were a no-first-use commitment and building a credible but minimum nuclear arsenal.

The pledge, to “study in detail India’s nuclear doctrine, and revise and update it, to make it relevant to challenges of current times”, gave no specifics but raised concerns among former U.S. diplomats that the policy of no first use would be abandoned. The State Department itself declined to comment.

Two sources involved in the manifesto’s drafting said the BJP wanted to reconsider the no first use policy in the wake of advances made by Pakistan in tactical nuclear weaponry.

Pakistan does not have a no first use policy and is building a nuclear weapons program designed to deter India and neutralize its much larger conventional military.

India also has concerns about China, which has a bigger military and more advanced strategic weapons. Some members of the strategic establishment said it had been 10 years since the doctrine had been released and it was time to revisit it.

Commenting on the election, which is being held in stages until May 12, Modi stopped short of saying the BJP would secure an outright majority, but described the electoral alliances it had struck with 25 other parties as “unprecedented”.

“People used to say that the BJP was untouchable,” said Modi, adding: “I don’t believe in political untouchability.”

FOCUS ON RIOTS

He said the continued media interest in his role in the 2002 Gujarat riots amounted to an attempt by journalists to smear him, but it had not worked.

“If the media had not made such an effort to malign Modi, Modi would not be as well known as he is,” said the 63-year-old politician, who sported a tangerine waistcoat, lime shirt and a large badge depicting a saffron flower, his party’s symbol.

Even though a Supreme Court inquiry found he had no case to answer over the riots, Congress campaign leader Rahul Gandhi said this decision should not absolve him of responsibility.

Modi has also faced accusations that he has been reticent over the killings because expressing contrition might alienate the BJP’s core Hindu vote in the five-week election. Results are due on May 16.

Modi said that his attempts to explain the 2002 events to journalists had proved futile.

“There is no top journalist to whom I have not given an interview. I answered every question from 2002-2007,” he said. “Later I saw that this was not an attempt to learn the truth.

“I have said what I had to say. Now I am in the people’s court, and I am waiting to hear its judgment.”