The shipment is made up of 120,000 doses of vaccines developed by the Gamaleya Research Institute, based in Moscow, Daily News newspaper reported.
The vaccines will be administered to people who have received the first shot of Sputnik V, the source added.
So far, Sri Lanka has reported 502,758 Covid-19 cases and 12,022 deaths.
A total of 431,036 people have recovered from the pandemic on this island from the Indian Ocean for a 85.7% recovery rate.
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