The Kremlin’s ambitions to win soft-power dividends around the world from Russia’s COVID-19 vaccine are being hampered by delays in delivering Sputnik V to foreign buyers clamoring for supplies.

This week, Guatemalan President Alejandro Giammattei said his country would seek to replace 8 million planned doses with supplies from other producers by the end of year after delays receiving its initial order.

Countries that embraced Sputnik amid a global rush to secure vaccines are increasingly reporting supply problems with the second component in the two-shot inoculation. In Argentina, a presidential adviser said the shortages put the government at risk as people were unable to receive the second dose within the recommended period of three months after the first.