Japan has approved the use of coronavirus vaccines that target Omicron for people aged 12 or older who have received their first two shots.

The so-called bivalent vaccines, made by US drug makers Pfizer and Moderna, are designed to target the initial coronavirus strain and the BA.1 Omicron subvariant. It is also expected to be effective against the prevailing BA.5 type.

A panel of experts at the health ministry on Monday cleared the use of the vaccines. This comes after Pfizer and Moderna both applied for authorization in August.

The decision allows people 12 years or older to receive an additional shot of the Pfizer jab, and people 18 or older to get a Moderna booster at least five months after their most recent shots.

The ministry expects around 68.5 million people to be eligible for the Omicron-targeting jab by October.

Elderly people and healthcare workers will be among the first to receive the booster in a campaign set to kick off as early as next Monday.

The ministry has asked municipalities across the country to gradually expand the scope of those eligible for the jab, with progress in their respective vaccination efforts in mind.

The ministry says it will study a proposal from some of the panel members to shorten the five-month period between the second and third doses.