Japan is looking into the possibility of mixing shots of AstraZeneca Plc's Covid-19 vaccine with those developed by other drugmakers in a bid to speed up its vaccine rollout, according to the minister in charge of vaccinations.

"I have asked the health ministry to come up with an opinion about the use of AstraZeneca vaccines for the first dose and Pfizer's with the second, or AstraZeneca's as the first shot and Moderna as second," vaccine programme chief Taro Kono said on the Fuji Television network.

He said this could speed up the vaccination rollout by shortening the intervals between the first and second shots when using the AstraZeneca vaccine, Reuters reported.