Nearly one million Hindu worshippers are expected to gather on the banks of the Ganges river this Friday and Saturday for a holy bathe despite galloping Covid-19 infections across the country, an Indian official has told Reuters.

Tens of thousands of pilgrims have already reached the site of the annual Ganges ritual on an island in the eastern state of West Bengal, which is reporting the most number of cases in the country after Maharashtra state in the west.

"The crowd may swell to anywhere between 800,000 to one million. We are trying to implement all Covid protocols," Bankim Chandra Hazra, a West Bengal minister in charge of organising the festival known as the Gangasagar Mela, told Reuters.