Japan's health ministry has decided to begin offering new coronavirus vaccines that target Omicron subvariants in mid-October at earliest.

The plan was discussed by the ministry's panel of experts on Monday.

The so-called bivalent vaccine combines ingredients used for existing coronavirus shots and those that are derived from the BA.1 subtype of the Omicron variant.

The vaccines are believed to demonstrate a high immune response against the Omicron sub-variants, including the BA.5, which is responsible for the current surge in infections.

The vaccines are currently being developed by Pfizer and Moderna.

Following clinical approval, the ministry plans to begin importing the vaccines in September for distribution to municipalities.

Officials say the vaccines will prevent serious conditions among the elderly and boost the overall immunity of Japanese society.

The vaccines are to be administered to all residents that have completed their first two shots. The ministry has not said how long of an interval after a previous vaccination would be needed for people to receive the new vaccines.

Members of the ministry's expert panel on Monday expressed concern that members of the public may refrain from taking their booster shot and wait till October to be administered the latest vaccines.

They called on people aged 60 or over who are currently eligible for their fourth shot to complete the process as quickly as possible.