WHO and partners have included nine experimental COVID-19 vaccines within an investment mechanism it is encouraging countries to join, known as the Covax facility. The initiative allows countries to invest in several vaccines to obtain early access, while theoretically providing funding for developing countries.

“We don't have sufficient information at this point to make a judgment” on the Russia vaccine, said Dr. Bruce Aylward, a senior adviser to WHO's director-general.

“We're currently in conversation with Russia to get additional information to understand the status of that product, the trials that have been undertaken and then what the next steps might be.” This week, President Vladimir Putin announced Russia had approved a coronavirus vaccine that has yet to complete advanced trials in people and claimed, without evidence, the immunization protects people for up to two years.