He added that he expected to be able to get 10 million doses of vaccines each week in May but that the Olympics, which a majority of Japanese have said should be postponed or cancelled, were not a factor in his scheduling.
Most of Japan's stock of syringes consists of regular versions that can draw just five doses from each vial, sparking fears that millions of doses could be wasted.
"This will enable us to start vaccination of the initial group of medical workers. We will need to fix the schedule for the rest of the medical workers and the elderly as we go forward," Kono told a regular news conference.
Once delivered, the vaccines must be administered by already overstretched medical workers. A Kyodo News survey showed about 80% of prefectural governments were concerned about having enough staff to give injections.
Prime Minister Yoshihide Suga's government put priority on the coronavirus response and economic revival over fiscal reform as it has rolled out a combined $3 trillion in economic packages -- two-thirds the size of Japan's gross domestic product.