AFP/ New Delhi

New Delhi's new chief minister Arvind Kejriwal announced on Wednesday his government will halve power bills and provide free water to poorer households after his anti-corruption party won a landslide election this month.

Households in the Indian capital consuming less than 20,000 litres of water per month will pay nothing from March 1, while those using less than 400 units of electricity will see their bills halved, the party's deputy chief minister told a news conference.

"We did what we said. Have halved the power rates and made water free... will also fulfil other promises, just keep giving us your support," Kejriwal said on Twitter in Hindi.

The populist policies are the first since Kejriwal won power and fulfil pledges he made during the election campaign to help millions of struggling families in the Indian capital make ends meet.

Kejriwal's government estimates the measures will cost about $270 million annually, but did not detail how they will be paid for.

Kejriwal's upstart Aam Aadmi (Common Man) Party, or AAP, trounced Prime Minister Narendra Modi's Bharatiya Janata Party (BJP) at the polls, handing the premier his first defeat since storming to victory at last year's general election.

The win capped a remarkable comeback for Kejriwal, whose last stint as New Delhi's chief minister lasted just 49 days and ended in chaos when he quit a year ago.

Deputy Chief Minister Manish Sisodia estimated that the party's new power policy would benefit about 3.6 million households, while the water offer would help 1.8 million.

"None of the previous administrations made any effort to give cheap, affordable power and water to the people of Delhi... we are doing it just as promised," Sisodia said.

The AAP, which was born out of an anti-corruption mass movement three years ago, announced similar decisions during its brief, controversy-marred rule last year.

Many critics have said giving out free water will encourage wastefulness in a country where water is already in a short supply.