The estranged wife of Indian Prime Minister Narendra Modi sought details about her security cover Monday, voicing concerns about her safety as her family demanded that she be treated as the country's "first lady".

The premier, who swept to power in May as head of the right-wing Hindu nationalist Bharatiya Janata Party, and Jashodaben were wed in an arranged marriage as teenagers.

But his family says it was only a "formal ritual" as Modi left her soon after. They were never divorced.

"I am the wife of the honourable prime minister of India," stated the retired school teacher in a Right To Information (RTI) application filed in western Gujarat state, where she lives with her brother.

"I would like to know under what provisions of the law and the constitution of India am I being provided protection? As wife of the prime minister what are the other benefits I am entitled to?"

India's RTI Act, similar to the Freedom of Information law in the United States, gives citizens the right to access information held by public bodies.

Modi's wife has long kept a low profile and rarely been photographed or interviewed. Modi guards his privacy zealously.

Her brother, Ashok Modi, said the government should provide her a car and women commandos because she is not comfortable with male guards.

"She is the 'first lady' and is entitled to get all the facilities," he was quoted as saying by the Hindustan Times newspaper, adding, "She deserves to be with (Modi) in Delhi."

Jashodaben stated in her application that "she travels by public transport while her body guards travel by official vehicle", the paper reported.

Modi's wife said she was worried about her safety, noting former prime minister Indira Gandhi was shot dead by her own security guards in 1984.

"Gandhi was attacked and killed by her personal bodyguards, because of which I am very afraid. Kindly provide me with details of the guards," she wrote in her application.

The grey-haired woman demanded a reply in 48 hours, calling it a "matter of life and death", signing the application using the name "Jashodaben Narendrakumar Modi".

In a rare interview before Modi became prime minister, Jashodaben, who gets a monthly government teacher's pension, said she read everything about him "I can get my hands on" but added, "I don't think he will ever call me".

Modi allegedly kept the wedding secret because it meant he would not be able to climb the ladder of a hardline Hindu group to which he belonged that frowned on key workers marrying, according to a Modi biography by author Nilanjan Mukhopadhyay.

Modi, earlier chief minister of Gujarat for over a dozen years, acknowledged his marriage for the first time when filing his general election nomination papers.