India’s government on Wednesday defended its decision to double the gap between the two doses of the AstraZeneca COVID-19 vaccine to up to 16 weeks, after three scientific advisers said there was no agreement on such a wide interval.

Reuters reported on Tuesday that the government increased the gap last month without the approval of the scientific group that it said recommended the move, citing three members of the National Technical Advisory Group on Immunisation (NTAGI) advisory body.

In multiple statements on Wednesday, the government said the interval was increased based on scientific evidence after thorough discussions among members of NTAGI as well as its working group on COVID-19 in two meetings held in May.

The AstraZeneca shot, made locally and branded Covishield, accounts for nearly 90% of the 259 million doses administered in India, where some states have curtailed vaccination programs over supply constraints.

The committee advised that “as per the COVID-19 working group recommendation, a dosing interval of a minimum three months between two doses of Covishield vaccine was recommended”, the government said in a statement.