Moscow, Aug 14 : A top respiratory doctor quit the Russian health ministry's ethics council after the country decided to go ahead with the registration of a Covid-19 vaccine even before conducting a crucial Phase 3 trial, MailOnline reported. It appears that Professor Alexander Chuchalin wanted to block the registration of the vaccine on "safety" grounds, before quitting the ethics council, said the report on Thursday. Russian President Vladimir Putin announced on Tuesday that the country had registered the world's first Covid-19 vaccine. Later on Wednesday, Russian Health Minister Mikhail Murashko said that the country will start the production of the vaccine within two weeks. However, the country has faced criticism from different quarters for rushing the vaccine into production. The World Health Organization (WHO) does not have sufficient information about the vaccine to comment on its effectiveness, an official of the UN health agency said on Thursday. Chuchalin's resignation suggests that the vaccine, dubbed "Sputnik V", faced criticism from within the country also. The MailOnline report also said that no specific reason was given for his resignation. However, shortly before he quit, Chuchalin in an interview with journal Nauka i Zhizn (Science and Life) underlined the importance of ensuring safety before approving any drug or vaccine. "In the case of a drug or vaccine, we, as ethical reviewers, would like to understand, first of all, how safe it is for humans," Chuchalin was quoted as saying in the interview. /IANS