NEW DELHI (REUTERS) - India has administered more Covid-19 vaccine doses in the last two weeks than the number of people who signed up for shots during the period, government data showed on Tuesday (June 29), signalling improving supplies after widespread shortages.

Indians struggled to book scarce inoculation slots after Prime Minister Narendra Modi opened up vaccinations to all of the country's 930 million to 940 million adults last month without a corresponding rise in output. Many immunisation centres ran out of vaccine shots and closed temporarily.

But rising production at the Serum Institute of India, the world's biggest vaccine maker, has boosted availability of Covid-19 shots in the country this month.

The company is on course to raise monthly output of the AstraZeneca vaccine to 100 million doses or more from July, from about 90 million this month and about 65 million in May.

That has helped India administer 61 million doses in the last two weeks starting June 12, compared with 58 million registrations for vaccination on the government's Co-Win vaccination website.

It was the first time vaccinations exceeded registrations since the immunisation drive was expanded from May 1.

India has administered 323.9 million doses, the most in the world after China and the United States. Vaccination relative to people, however, is much lower in India than in many countries.

So far, more than 346 million people have registered for shots in India, which wants to cover all its adults this year.

Currently, cities are vaccinating much faster than the countryside.

India has stepped up inoculations since last week when Mr Modi's federal government took back the responsibility of supplying doses to individual states free of cost.

A previous policy of letting states buy a portion of their requirements from companies had slowed down the immunisation process.