India opened up its COVID-19 vaccination drive to people above 45 on Thursday as infections rise, which will delay vaccine exports from the world’s biggest maker of the drug.

The country, with the most number of reported coronavirus infections after the United States and Brazil, has so far administered 64 million shots and exported almost as many. This has raised criticism at home as India’s per-capita vaccination tally is much lower than several countries.

The government has previously said that people over 45 can register for vaccination from April 1.

India initially focused on front-like workers, the elderly and those suffering from other health conditions, unlike some richer countries that have made all their adults eligible to receive the vaccine.

New Delhi says it is working towards that goal, and Health Minister Harsh Vardhan tweeted that there would be no vaccine shortage in the country as it opens up the inoculation program.

“Center to continually replenish states’ supplies,” he said on Twitter. “Avoid overstocking and under stocking.”

India has already decided to delay big vaccine exports for the time being, including to the WHO-backed global vaccine alliance COVAX.

It is currently using the AstraZeneca vaccine and a dose developed at home by Bharat Biotech, which is struggling to step up supplies. India’s drug regulator is soon expected to approve Russia’s Sputnik V vaccine.

India has registered over 12 million COVID-19 cases, including a big surge last month. Deaths stand at more than 162,400.