The world's largest vaccine maker, the Serum Institute of India, has resumed exports of Covid-19 shots, it has said, in a boost for poorer countries that have struggled to secure supplies.

The shipment to Tajikistan under the Covax vaccine-sharing initiative agreement was the company's first in seven months, reports AFP.

“This will go a long way in restoring vaccine supply equality in the world,” tweeted billionaire chief executive Adar Poonawalla.

“It's a huge moment to begin exports again, for us, our partners at Covax and the low- and middle-income countries we support,” he added in a separate statement.