Prime Minister Narendra Modi was meditating on a rocky outcrop off India's coast on Friday in a final appeal to his Hindu voter base as marathon national elections drew to a close.

Modi remains roundly popular and is widely expected to win a third term when the poll concludes, in large part due to his cultivated image as an aggressive champion of the country's majority faith.

Modi's decade in power has seen the leader engage in regular meditations, fasts and temple visits to burnish his religious credentials, despite India's secular constitution.

The 73-year-old arrived late Thursday at a monument to Swami Vivekananda, a renowned 19th-century Hindu monk and philosopher, for his latest ritual.

Images published by Modi's ruling Bharatiya Janata Party (BJP) showed the premier sitting cross-legged with his eyes closed and one arm clasping prayer beads.

Local media reports said around 2,000 police and security personnel were guarding the site in the southern state of Tamil Nadu for the two-day meditation, which concludes Saturday on the final day of general election voting.

Modi underwent a similar retreat immediately before his last election victory in 2019, when he spent days meditating inside a cave in the Himalayan foothills.

This year he presided over the inauguration of a grand temple to the deity Ram, built on the grounds of a centuries-old mosque in Ayodhya razed by Hindu zealots in 1992.

Construction of the temple fulfilled a longstanding demand of Hindu activists and was widely celebrated across the country with back-to-back television coverage and street parties.

The BJP and Modi are widely expected to win this year's election, which is conducted over six weeks to ease the immense logistical burden of staging the democratic exercise in the world's most populous country.

The ascent of Modi's Hindu-nationalist politics has made India's Muslims increasingly anxious.

Modi has made a number of strident comments against India's 200-million-plus Muslim minority since voting began last month, in an apparent effort to galvanise support.

He has used public speeches to refer to Muslims as "infiltrators" and "those who have more children", prompting condemnation from opposition politicians.