The Cabinet has decided to purchase nine million doses of the Sinopharm vaccines and 14 million doses of the Pfizer jabs to vaccinate thoese aged between 18 and 30.
At present, Sri Lanka is vaccinating only those above 30 years of age.
A Cabinet spokesman said the vaccination programme was initially started to inoculate 14 million by August 9. However the country had received 19.49 million doses and 11.26 million were used as the first dose and 3.25 million doses.
Last month, President Gotabaya Rajapaksa's senior advisor Lalith Weeratunga stated that the government was planning to vaccinate school children between the ages of 12 and 18 years against Covid-19 using the US-manufactured Pfizer and Moderna vaccines.
Sri Lankan schools have been closed for nearly one and half years.
Meanwhile amidst daily increasing deaths and cases, the governmenthas tightened health guidelines from Thursday allowing only one person to leave the house.
The Director General of Health Services, Asela Gunawardena issuing a fresh set of guidelines stated that all private and public education institutions, universities, indoor sports complexes, swimming pools, and spas will be closed from today.
Children's parks, carnivals, concerts, beach parties and beach gatherings have also been banned.
However hotels and resorts were allowed to open for only 25 per cent of the total capacity, while shopping malls and supermarkets too were allowed only 25 per cent. In addition, an island-wide overnight quarantine curfew from 10 p.m. to 4 a.m. will also be in force.
For a second consecutive day, Sri Lanka recorded 170 deaths with 3,660 new cases.
Health experts, trade unions and all opposition parties are demanding the government to lock down the country for two weeks to save the healthworkers from the fast spreading Delta variant.
A number of cities have been voluntarily closed by citizens and traders for a week while the Mayor of capital Colombo urged people to not to enter the city as 98 per cent of those infected there were found with the Delta variant.
Rosy Senanayake urged shops except those providing essential services be closed for two week.
"We are in a very dangerous situation. Though we have a good health system, our capacity have been exceeded and there only limited number of ICU beds available."
In a shocking prediction, the Monash University in Australia in collaboration with World Health Organization's SEAR and Sri Lanka County Office projected that the number of Covid cases would increase up to mid-September at 6,000 cases per day, deaths up to early October coming to a peak at around 220 per day.
The joint team which made the estimation using Sri Lanka's Epidemiology Unit data warned that ICU admission will peak at around 275 by early October with cumulative deaths around 30,000 by January 2022.