Sri Lanka, Sept. 18 -- India administered more than 20 million Covid vaccine doses in a day on Friday in a record-breaking effort to mark PM Narendra Modi's 71st birthday.

The effort surpassed the country's previous daily record of more than 13 million doses on 27 August.

India aims to vaccinate all eligible Indians by the end of 2021 but experts say the drive needs to pick up a consistent pace to meet the target.

It has so far given more than 790 million doses of three approved jabs.

More than half of India's eligible population - some 594 million people - have received at least one dose of a Covid vaccine, according to official data.

But only about 20% of eligible adults have been fully vaccinated since the beginning of the drive i...