Narendra Modi, the Indian prime minister, has laid the foundation stone for what is set to be the world's tallest statue nearly four kilometres into the sea off Mumbai, as its projected cost and environmental impact drew criticism.

The 192-metre statue of Chhatrapati Shivaji, a medieval Hindu ruler in the western state of Maharashtra who fought the Muslim Mughal dynasty and carved out his own kingdom, is expected to be completed by 2019.

To be built at a cost of about $530m, it will be more than twice the size of the Statue of Liberty in New York and five times higher than Christ the Redeemer in Brazil's Rio de Janeiro.

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"Even in the midst of struggle, Shivaji Maharaj remained a torchbearer of good governance," Modi said at the inaugural event on Saturday.

"So many aspects of his personality inspire us."

Environmentalists claim the project would involve reclaiming land and disturbing the fragile marine ecosystem along the coast [Danish Siddiqui/Reuters]

The government of Maharashtra state, of which Mumbai is the capital, has come under criticism for the project.

By Saturday evening, about 27,000 people had signed a Change.org petition asking that the government spend the money on infrastructure and development instead.

"Apart from a waste of money, this statue is going to be terrible for the environment, for the traffic situation in South Bombay and a security nightmare," the petition said.

Environmentalists claim the project would involve reclaiming land and disturbing the fragile marine ecosystem along the coast.

"Marine life would be impacted and fishermen would be hard hit," Stalin Dayanand of non-profit Vanashakti said.

The 17-hectare area on which the project is planned was a prime fishing area and the construction would affect the livelihood of hundreds of thousands of fishermen, Damodar Tandel of local fishermen's union AMMKS said. 

More than 50 fishermen, who were protesting against the proposed memorial, were arrested before the foundation laying ceremony on Saturday, according to the news website thewire.in.

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"How can we think about the cost when it comes to building a memorial for Shivaji Maharaj?" Maharashtra chief minister, Devendra Fadnavis, recently said in the state legislative assembly. 

"He is our pride and it is only fitting that we should build a grand memorial in his name."

Shivaji is revered by many in Maharashtra. Mumbai's main train station and airport are named after the ruler, who is also one of the symbols of a Hindu cultural revival promoted by Modi.

Patel statue

This is not the first time that a large amount of taxpayer money has been set aside to build a massive statue or memorial to a popular leader in India.

In 2014, shortly after Modi became prime minister, the national budget set aside about $34m to build a massive structure to honour independence leader Vallabbhai Patel.

That project is under way in Modi's home state of Gujarat. Once complete, it is expected to cost about 10 times the amount set aside in the budget. The rest is expected to be filled by private and corporate donations.

Source: Al Jazeera and news agencies