Russia has announced progress in its Sputnik suite of Covid-19 vaccines, with a new version aimed at children and a nasal spray that President Vladimir Putin said he has taken as a booster.

According to Reuters, Putin said in televised comments that he had been re-inoculated six months after his initial dose of the Sputnik V vaccine because his antibody levels had dropped. He said the booster took the form of an injection, followed the next day by a powder sprayed into both nostrils.

“That was all — I didn't feel anything. Nothing. Today, after these two procedures, I already did some sport in the morning,” he said.

Kirill Dmitriev, the head of the Russian Direct Investment Fund (RDIF), which invested in Russia's flagship vaccine and markets it overseas, said Russia would sell the nasal form to other countries next year.