More than two billion doses of coronavirus vaccines will likely be available in India between August to December this year, a top government adviser has said.

Those doses would include 750 million of AstraZeneca's vaccine, produced in India by the Serum Institute of India, as well as 550 million doses of Covaxin, made by Bharat Biotech, government adviser V K Paul told reporters at a news conference.

Several Indian states are reporting an acute shortage of vaccines, even as coronavirus cases surge across the country.