Russia's Sputnik V vaccine has sown division among former Eastern Bloc countries, analysts say, with some seeing it as a godsend and others as a Kremlin propaganda tool.
Countries in the region have been particularly hard hit by the virus and find themselves torn between a readily available jab from their old ally and European Union resistance to Russian influence.
Analysts say such discord benefits Russia and its efforts to sow disorder in the region since the Soviet Union crumbled three decades ago.
"It is very clear that Sputnik V has become a tool of soft power for Russia," Michal Baranowski from the German Marshall Fund of the United States told AFP.
"The political goal of (Russia's) strategy is to divide the West," said Baranowski, who heads the Fund's Warsaw office.
Slovakia found itself facing a government crisis only days after receiving its first batch of Sputnik V on March 1.
Prime Minister Igor Matovic hailed the jab, saying "Covid-19 does not know anything about geopolitics", while foreign minister Ivan Korcok called the vaccine "a hybrid war tool".
'Help my country'
The vaccine has 91.6% efficacy against Covid-19, according to a recent study published by The Lancet, and it is already being used in several countries around the world.
It is yet to be approved by the European Medicines Agency (EMA) for use in the EU but some ex-communist member states are planning to roll out the jab regardless.
EU members like Slovakia started to look east after Europe got off to a slower-than-expected start procuring Pfizer/BioNTech, AstraZeneca/Oxford and Moderna vaccines.
Experts agree rapid vaccination is the only way out of the coronavirus crisis, which is hitting Central and Eastern Europe particularly hard.
Slovakia and its neighbor the Czech Republic have had the worst per capita death rates in the world for weeks, according to AFP statistics based on official data, and hospitals across the former Soviet satellites are reaching capacity.
Czech President Milos Zeman asked his ally President Vladimir Putin for a Sputnik V supply in a letter last month.
"I think I will help my country this way," Zeman said.
When the Czech health minister refused to accept a vaccine lacking approval from the EMA, Zeman asked for his dismissal, a request that has not been carried out.
Kremlin 'rubbing its hands'
"The potential use of Sputnik V in the Czech Republic has become a purely political weapon," said Prague-based political analyst Jiri Pehe.
He dubbed the vaccine "a tool of political struggle and propaganda".
He said Russia has had problems producing enough Sputnik vaccines for its own needs and there were questions about the conditions in which the vaccine was produced.
"If Vladimir Putin really trusted the vaccine, he would be the first to get a jab with a great pomp, but he's giving it a wide berth," Pehe said.
Sputnik V's spread has led EU chief Charles Michel to say vaccines should not be used for propaganda purposes.
"We should not let ourselves be misled by China and Russia, both regimes with less desirable values than ours, as they organize highly limited but widely publicized operations to supply vaccines to others," Michel said earlier this week.
Pavel Havlicek, an analyst at the Prague-based Association for International Affairs, said the Kremlin was meanwhile "rubbing its hands".
"Russia's vaccine diplomacy clearly seeks to undermine the mutual trust and cohesion in Europe," Havlicek said.
'Very low trust'
The first and so far only EU country actually using Sputnik V is Hungary, whose Foreign Minister Peter Szijjarto got the jab himself to sway fellow Hungarians in favor of the vaccine.
Prime Minister Viktor Orban, who also fosters close ties with Putin, has received a jab from China's Sinopharm vaccine, which Hungary also became the first EU country to use last month.
Elsewhere in post-communist Europe, Serbia has become one of the world's fastest vaccinators using both Sputnik and Sinopharm, while another EU-hopeful Albania is planning to start talks on the supplies of both vaccines.
EU members Bulgaria, Croatia, Estonia, Latvia and Romania are in turn waiting for an EMA approval for Sputnik V, while Lithuania has ruled the vaccine out.
Poland, the largest former communist EU member, is in no mood to buy Sputnik V either.
"Russia has very clearly planted the Russian flag on the Sputnik V vaccine... and in Poland, something that has a Russian flag on it will not be received with open arms," Baranowski from the German Marshall Fund said.