India expects to receive three to four million doses of the Pfizer and Moderna Covid-19 shots through the Covax facility by August, two sources said, as it tries to expand inoculations to prevent another surge in infections.

Covax, led by the Gavi vaccine alliance and the World Health Organisation, could ship the US-made doses to India as early as this month, one of the sources aware of the discussions told Reuters.

"It's a donation through Covax," said the source. Both sources declined to be named as the discussions are private.