SEOUL: South Korea said on Saturday it signed a contract with Pfizer Inc to purchase an additional 40 million doses of its COVID-19 vaccine amid fears of spiking infections at home.

That brings the current amount of Pfizer vaccines to 66 million doses, it said in a statement.

It added that it had secured a total 192 million doses of vaccines, including those from Moderna Inc, AstraZeneca PLC, Johnson & Johnson's and Novavax.

"The government has acquired COVID-19 vaccines large enough to vaccinate approximately 100 million people...(which) is double the entire population of South Korea," Health Minister Kwon Deok-cheol told a briefing.

"(The government) will make all out efforts to achieve its promise to vaccinate 12 million people by end of June and achieve herd immunity by November," he said.

The deal comes a week after Pfizer agreed to supply additional vaccines to Japan by the end of September, which would be enough to inoculate all people over 16.

Nearly 2.2 million South Koreans out of a population of 52 million have received their first vaccine dose, bringing the vaccination rate to just above 4%. The government's goal is to reach 70% by November.

The low rate compares with a 41% rate in the United States, according to Reuters data.

A Gallup Korea survey on Friday showed for the first time negative views outweighing positive views over the government's handling of the pandemic and vaccinations - 43% had positive views versus 85% last May, when daily infections were in the single digits.

The country reported 785 new cases as of Friday midnight, bringing the total tally to 118,243 and 1,812 deaths.