Former Honduran President Manuel Zelaya is taking part in Phase 3 trials of a potential coronavirus vaccine.
Venezuelan state television showed Zelaya receiving a shot of Russia's experimental Sputnik V coronavirus vaccine in Caracas on Monday.
Venezuela is the first Latin American country to participate in the testing process.
Western experts raised questions over the Sputnik V vaccine’s readiness for mass trials, citing the fact that Russia had tested the vaccine on just a small sample group before launching widespread testing.
Venezuelan President Nicolas Maduro discounted the criticism, expressing satisfaction Zelaya is taking part in the trials.
So far, Venezuela has confirmed more than 87,000 coronavirus cases and at least 736 deaths.