India registered about 475,000 more total deaths in 2020 than the previous year, government data released months ahead of schedule on Tuesday showed, as the World Health Organization readies its estimates of excess Covid-19 deaths whose methodology New Delhi has opposed.

Some experts estimate India's actual Covid death toll is as high as four million, about eight times the official figure, especially as a record wave driven by the Delta variant killed many people in April and May of last year. The WHO's estimate will be published on Thursday.