Japan has signed a contract with U.S. pharmaceutical giant Pfizer Inc. to receive additional doses of its coronavirus vaccine for 25 million people by September, health minister Norihisa Tamura said Friday.

Combining the additional 50 million doses that the country will receive under the agreement with the 144 million doses under its previous contract with Pfizer, Japan will be able to inoculate 97 million people.

Prime Minister Yoshihide Suga agreed on additional doses in a phone call with Pfizer CEO Albert Bourla in April.

Suga said after the call that there would be sufficient doses by September for everyone in Japan aged 16 and above, roughly 110 million people.

The government is trying to accelerate its inoculation campaign, but it has administered at least one shot to just 3 percent of Japan's population of 126 million, the slowest vaccination rate among members of the Organization for Economic Cooperation and Development.

Japan has also signed coronavirus vaccine contracts with U.S. biotechnology company Moderna Inc. to receive 50 million doses, enough for 25 million people, and enough doses from Britain's AstraZeneca Plc for 60 million people.

But the double-dose vaccine developed by Pfizer and its German partner BioNTech SE is currently the only COVID-19 vaccine approved for use in Japan.

The Ministry of Health, Labor and Welfare is expected to deliberate on the approval of the Moderna and AstraZeneca vaccines on May 20.

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