BUDAPEST, Hungary (AP) —Starting Monday, the United States plans to reopen to foreign travelers who are fully vaccinated against the coronavirus. But non-immigrant adults need to have received vaccines authorised by the Food and Drug Administration (FDA) or which received an emergency use listing from the World Health Organization (WHO).

That leaves many hopeful travelers across the globe who have taken full courses of vaccines widely used in other parts of the world including Sputnik V and the China-produced CanSino jab, in particular — scrambling to get reinoculated with shots approved by US authorities.

While Sputnik V is used in around 70 countries worldwide, it has still not been approved by either the FDA or the UN health agency. 

Two other Chinese vaccines, Sinopharm and Sinovac, have been approved by the WHO and will thus be accepted for travel into the US.

Mexico received nearly 12 million doses of CanSino and almost 20 million of Sputnik V after shipments began earlier this year. Residents who got the required two shots of those vaccines now are looking to top up with shots of the Pfizer, Moderna, AstraZeneca or Johnson & Johnson vaccines, hoping that will make them eligible to cross the border.

Nearly 1 million people have received the Sptnik V vaccine in Hungary, a Central European country of around 10 million. Hungary was one of only two countries in the 27-member European Union to roll out the Russian vaccine. Fewer than 20,000 people received it in Slovakia.

Citizens of Russia, where use of Sputnik V is most widespread, also are seeking Western-approved shots so they can travel abroad.

Russia, which unveiled Sputnik V with much fanfare as the world’s first registered vaccine in August 2020, criticised US plans to leave the vaccine off its list of approved shots.

“There are exactly zero reasons for such decisions,” Leonid Slutsky, chairman of the foreign relations committee in the Russian Duma, or lower house of parliament. “The effectiveness and safety of the Sputnik V vaccine has been proven not only by specialists, but also by its practical application.”

But the WHO is still reviewing the vaccine, and months of holdups make it unclear when Sputnik V might receive an emergency use listing.

Meanwhile, Hungary’s government has made bilateral agreements with 24 countries — including Russia, Serbia, Mongolia, Georgia, and Kazakhstan — on mutually recognising proof of vaccination, regardless of vaccine type. Hungary’s Ministry of Foreign Affairs told The Associated Press that it is open to a similar agreement with the United States, but “currently there is no ongoing negotiation.”