Tokyo, May 24 : The Japanese government on Monday opened large-scale inoculation centres in Tokyo and Osaka waimed at speeding up the country's sluggish Covid-19 vaccination rollout. With just two months to go until the Tokyo Olympics and with the country's vaccination campaign the slowest among OECD countries, the government has enlisted Self-Defense Forces' (SDF) doctors and nurses to operate the facilities for three months, reports Xinhua news agency. The SDF personnel will be administering jabs using the newly-approved Moderna Inc Covid vaccine, developed in the US and formally approved here on May 21. Up until now Japan had only been using the vaccine developed by Pfizer, but the government has also approved the use of Britain's AstraZeneca Plc., although jab may not be rolled out immediately amid concerns over extremely rare instances of blood clots. The government is hoping that the two mass vaccination centres will be able to compete administering the vaccinations to 36 million seniors aged 65 or older by the end of July. The centres will be accepting reservations for jabs from seniors living in prefectures neighbouring those where the large-scale facilities are located, the Health ministry has said. "The government will continue to make all-out efforts so that as many people as possible can be inoculated as quickly as possible," Chief Cabinet Secretary Katsunobu Kato told a press briefing on the matter. Japan began inoculating its elderly population of about 36 million in April, after its vaccination campaign for health care workers started in February. Japan has the lowest rate among OECD countries of administering vaccinations to its population of 126 million people and according to recent government data, the nation had administered at least one shot to around just 4 per cent of its population. Meanwhile, multiple municipalities have said they expect to miss the government's end-of-July deadline to finish inoculating the elderly, due to a lack of healthcare workers available to administer the shots and reservation systems being plagued with technical issues. /IANS