The Serum Institute of India (SII) has sought India's drug regulator's approval for the Covishield vaccine as a booster dose citing adequate stock of the vaccine in the country, officials informed ANI on Thursday.

According to the officials, the demand has been made due to the emergence of a new coronavirus variant 'Omicron'. The Serum Institute of India is the first Indian company to seek approval for the Covid-19 booster dose.