President Vladimir Putin’s announcement in August that Russia had cleared the world’s first COVID-19 vaccine for use before it even completed safety trials sparked skepticism worldwide. Now he may reap diplomatic dividends as Russia basks in arguably its biggest scientific breakthrough since the Soviet era.

Countries are lining up for supplies of Sputnik V after peer-reviewed results published in The Lancet medical journal last week showed the Russian vaccine protects against the deadly virus about as well as U.S. and European shots, and far more effectively than Chinese rivals.

At least 20 countries have approved the inoculation for use, including European Union member-state Hungary, while key markets such as Brazil and India are close to authorizing it. Now Russia is setting its sights on the prized EU market as the bloc struggles with its vaccination program amid supply shortages.