Women walk past India's new parliament in New Delhi on Wednesday. Reuters

The proposed law would reserve one-third of seats in India's lower house and state assemblies for women once it takes effect, which could take until at least the end of the decade.

It would not take effect before national elections next year but will be a further fillip to the already commanding position of Prime Minister Narendra Modi's party ahead of that poll.

A total of 454 lawmakers voted for the bill, with only two against.

"The proposal has been passed with more than a two-thirds majority of the members present in the house," said Om Birla, the speaker of parliament.

When prime minister Indira Gandhi took office to lead India in 1966 she became the world's second woman head of government in a parliamentary democracy, following Sri Lanka's Sirimavo Bandaranaike six years earlier.

Two women have served in India's ceremonial presidency and others have been chief ministers, party leaders and powerbrokers in the decades since, but that has not equated to broader political representation.

Just 104 of India's 788 MPs were women after the last national election, according to government figures - a little over 13 per cent.

Those figures reflect a broader under-representation of women in Indian public life.

Just under a third of working-age Indian women were in the formal labour force last year, according to government data.

Six earlier attempts to pass the bill stalled in the decades since it was first introduced in 1996, with sometimes vehement resistance from lawmakers.

Mulayam Singh Yadav, at the time the chief minister of India's most populous state, suggested in 2010 that the bill should not be passed because it would compel men to wolf-whistle at their female colleagues in parliament.

The bill proposes a constitutional amendment to enshrine a one-third quota reserved for women, requiring a two-thirds majority in both houses of parliament to succeed.

Its passage through the upper house is expected to be smooth thanks to broad political support for the measure.

The quota would only take effect once India redraws its electoral boundaries after the mammoth undertaking of a census for its 1.4 billion people - the last due in 2021 was postponed indefinitely because of the coronavirus pandemic.

Sonia Gandhi of the opposition Congress party told parliament her colleagues supported the bill but called for revisions to allow it to take effect sooner.

"Immediate implementation of the bill is not only necessary but also possible," she said.

"Any delay in implementing it will be injustice to women."

Several Asian countries have laws mandating a minimum number of women lawmakers in national parliament, including India's neighbours Nepal and Bangladesh.

Just four Asian nations - Malaysia, Japan, Sri Lanka and the Maldives - have a lower proportion of women MPs than India, according to World Bank data from last year.

Modi's Bharatiya Janata Party (BJP), widely expected to win next year's election and deliver him a third term in office, already enjoys strong support among women.

An exit poll conducted by news outlet India Today after the last election in 2019 found 46 per cent of Indian women voted for the BJP and its coalition allies, against 44 percent of men.

Agence France-Presse