The officials - who requested anonymity - said a few vaccine candidates were likely to get emergency-use authorisation from the drug regulator in the "next few weeks".
Two companies have already applied for consideration, and six more are in various stages of clinical trials.
The vaccination programme aims to reach 300 million people by early August.
India has recorded nearly 10 million Covid-19 cases, and more than 144,000 deaths from the disease so far. The vaccination roll-out plans are being made even as the contagion shows marked signs of a slowdown.