President Vladimir Putin has heralded Russia's vaccine offering as "reliable as a Kalashnikov assault rifle".
The comment was made during a video conference on Thursday with Deputy Prime Minister Tatyana Golikova.
It came as the country's health officials registered a single-dose version of the Sputnik V vaccine on Thursday, dubbed Sputnik Light.
Mr Putin's comparison referenced the Soviet Union-era weapon that remains popular and widely used still today.
He was quoting a comment originally made by an Austrian doctor earlier this year about the jab's efficacy.
The Sputnik V vaccine works in a similar way to others developed by Oxford/AstraZeneca and Janssen/Johnson & Johnson. It uses a cold-type virus, engineered to be harmless, as a carrier to deliver a small fragment of the coronavirus to the body.
The two-dose version of the jab has now been authorised in dozens of other countries around the world.
Sputnik Light, a single-use version where recipients only get the first jab, was officially authorised in Russia on Thursday.
In a press release, its makers said a single dose had demonstrated 79.4% efficacy during the country's vaccine roll-out.
the statement said.
The authorisation comes amid an ongoing international row over whether patents should be waived on vaccine technology to boost production.