Moments after Russia announced a coronavirus vaccine, the World Health Organisation said that it would not give its stamp of approval without a rigorous safety review. “We are in close contact with the Russian health authorities and discussions are ongoing with respect to possible WHO pre-qualification of the vaccine,” the United Nations health agency’s spokesman Tarik Jasarevic told reporters in Geneva at an online press briefing.

Jasarevic added that the pre-qualification of any vaccine requires rigorous review and assessment of all the safety and efficacy data.

Earlier on Tuesday, President Vladimir Putin announced that Russia had developed the first coronavirus vaccine in the world. Putin claimed that the vaccine offered a “sustainable immunity” against the new coronavirus.

Russia’s Sputnik V vaccine has been developed by the Gamaleya research institute in coordination with the country’s defence ministry.

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A total of 165 candidate vaccines are being worked on around the world, according to the latest WHO overview produced on July 31.

Of those, 139 are still in pre-clinical evaluation, while the other 26 are in the various phases of being tested on humans, of which six are the furthest ahead, having reached Phase 3 of clinical evaluation.

The Gamaleya candidate being produced in Russia, which is among the 26 being tested on humans, is listed as being in Phase 1.