In recent weeks, authorities started vaccinating medical personnel and senior citizens using doses provided by Russia and China
Venezuelan officials said on Thursday the country's government has been unable to complete a payment required to receive coronavirus vaccines because transfers to the global Covax vaccine program had been blocked.
The government of President Nicolas Maduro for months said it was unable to pay for the Covax program because of US sanctions, and then in March announced that it had made almost all the required $120 million payment.
Vice President Delcy Rodriguez in a televised broadcast on Thursday said the government had been unable to pay down the remaining $10 million because four operations had been blocked.
"The financial system that also hides behind the US lobby, has the power to block resources that can be used to immunize the population of Venezuela," Rodriguez said.
Foreign Minister Jorge Arreaza later tweeted a copy of a letter from Covax saying it had received information from Swiss bank UBS that four operations, totaling $4.6 million, "were blocked and under investigation."
It was not immediately evident who blocked the operations or why.\
UBS, when asked for comment, said that for legal and regulatory reasons it is "unable to comment on matters relating to potential client relationships."
Covax did not immediately reply to a request for comment.
The Covax letter notes Venezuela has expressed interest in the Johnson & Johnson and Novavax vaccines.
Maduro's government this year began negotiating with opposition leader Juan Guaido to pay for Covax vaccines using funds frozen in the United States via Washington's sanctions against Maduro.
In March, Venezuelan officials announced they had managed to pay for the vaccines on their own, and have since backed away from talks over using the frozen funds.
In recent weeks, authorities have started vaccinating medical personnel and senior citizens using doses provided by Russia and China.
Participants have complained about confusion in the process, and opposition leaders say it lacks transparency.
Venezuela has reported 246,764 coronavirus cases and 2,764 deaths, although critics say the actual figures are likely higher due to underreporting and limited testing.