Moscow on Sunday confirmed its first case of the new UK coronavirus strain, despite an earlier decision by officials to suspend flights from Britain to stop the mutation reaching Russia.
One person returning to Russia from the UK was found to have been infected with the new strain, the head of Russia's health regulator Rospotrebnadzor told state-run television.
Watchdog head Anna Popova did not specify when the person tested positive for coronavirus or any other circumstances surrounding the discovery.
The B117 coronavirus strain is thought to have first emerged in south-eastern England late last year, and has since been detected in dozens of countries around the world.
Officials in Moscow temporarily suspended flights to and from the UK in December after a similar move by dozens of other countries.
Russia has one of the highest infection rates in the world and officials on Sunday confirmed a total of nearly 3.5 million cases.
Health officials last month admitted the country's virus toll was much higher than previously reported, making Russia the third-worst hit globally.
The Kremlin has placed its hope on the homegrown Sputnik V vaccine to counter the pandemic, instead of returning to lockdown measures being imposed in many other European countries.