Japan on Sunday approved its first coronavirus vaccine, clearing the way for mass inoculations as the nation prepares to host the postponed 2020 Olympics.

"The health minister today gave a special approval to the Pfizer vaccine," the prime minister's office said in a tweet.

Japan is now expected to put the Pfizer/BioNTech vaccine in the arms of 10,000 to 20,000 medical workers from as early as Wednesday, before making it and other coronavirus vaccines available for more medical workers and the elderly from April.

The government is yet to outline the exact rollout schedule for the rest of its population of 126 million people.

Pfizer vaccine
The Pfizer vaccine is pictured. AFP / THOMAS KIENZLE

Olympics officials have insisted that the Tokyo Games will take place even though Covid-19 continues to affect the entire world.

Athletes and other participants will be encouraged, but not obliged, to be vaccinated to take part.

Japan is now trying to secure enough special syringes that can extract the full six doses from each vial of the Pfizer vaccine.

More commonly used syringes can only draw five doses.