The third phase of vaccination against the coronavirus is likely to commence in March and will cover 27 crore people aged 50 years and above and those with co-morbidities, Health Minister Harsh Vardhan said in Lok Sabha on Friday.

Replying to questions on vaccines and the vaccination drive against the coronavirus during the Question Hour, Vardhan said nearly five million people have been inoculated in the country so far.

He added that the vaccination drive for frontline workers has begun this week.

"In coming days, 27 crore people who are of above 50 years of age and those under 50 with co-morbidities will be vaccinated," Vardhan said.

The vaccination drive began on January 16, starting with healthcare workers and then the frontline workers, both estimated to be around three crore.

"After the completion of first and second phases, the third phase could be launched from any week next month," Vardhan said.

He added that the third phase will cover people above the age of 50.

"It is not possible to give an exact date, but we estimate that this process can start in the second, third or the fourth week of March," he said.

Vardhan said the finance minister has allocated Rs 35,000 crore for vaccination in the budget and she has assured that it could be increased if required.

He said two vaccines -- Covishield, manufactured by the Serum Institute, and indigenously developed Covaxin of Bharat Biotech -- have been approved for emergency use authorisation.

Besides these, work is in progress on seven vaccines. Of the seven, three vaccines are in phase 3 clinical trial stage. Two vaccines are in phase 1 and 2 clinical trial stages and the remaining two are in advanced pre-clinical stage.

He said India has received requests for vaccines from 22 countries. These countries include Afghanistan, Algeria, Bangladesh, Bhutan, Brazil, Egypt, Kuwait, Maldives, Mauritius, Morocco, Mongolia, Myanmar, Nepal, Nicaragua, Oman, Saudi Arabia, Seychelles, South Africa and the UAE. There is also request from the Pacific Island countries, he said.

Vaccines have already been given to 15 countries through grant assistance and contracted doses.

He said 56 lakh doses have been sent through grants and five lakh doses through contract.