Buried deep in the dry, 72-page annual report of the U.S. Department of Health and Human Services lay a startling admission: U.S. health officials under President Donald Trump worked to convince Brazil to reject Russia’s Sputnik V coronavirus vaccine.

The document, released in January, drew little attention at first. But that changed on Monday when the official Twitter account for the Sputnik V vaccine posted a screenshot of the previously overlooked claim, citing a report by Brasil Wire, and criticized the United States for effectively blocking Russia’s attempts at vaccine diplomacy.

“We believe countries should work together to save lives,” the tweet read. “Efforts to undermine the vaccines are unethical and are costing lives.”

Brazil, which has the second-highest coronavirus death toll worldwide, has struggled to obtain adequate vaccine supplies. But the Health Attaché office within HHS’s Office of Global Affairs pushed the country to turn down offers of help from the Russians last year, according to the report.

Under a section titled “Combating malign influences in the Americas,” the HHS report states that countries including Russia “are working to increase their influence in the region to the detriment of US safety and security.” The global affairs office coordinated with other U.S. government agencies “to dissuade countries in the region from accepting aid from these ill-intentioned states,” it says.

In a Monday night statement, the U.S. Embassy in Brazil said that its diplomats “have never discouraged Brazil from accepting vaccines against Covid-19 that have been authorized by their respective regulatory bodies.” But that response didn’t amount to a full denial, since Brazilian regulators have yet to approve the Sputnik V vaccine.

An HHS spokesman told The Washington Post that the department is “not in a position to comment on vaccines that have not been authorized by the Food and Drug Administration for use in the U.S” or to “discourage Brazil or any other nation from accepting vaccines that have been authorized by their respective regulators.”

In a statement, Brazil’s Ministry of Foreign Affairs said that “the Embassy of Brazil in Washington has not received consultations or actions from United States authorities or companies regarding the possible purchase, by Brazil, of the Russian vaccine against Covid-19.”

Negotiations over vaccine purchases “have been guided by principles such as the sense of urgency and the sovereign choice of suppliers,” the statement said.

A Kremlin spokesman declined to comment directly on the HHS report on Tuesday, according to Reuters, but said that Sputnik V was never given a fair chance to succeed because so many countries are being urged not to buy it.

“In many countries the scale of pressure is quite unprecedented,” Kremlin spokesman Dmitry Peskov was quoted as saying.

Initial skepticism toward Russia’s coronavirus vaccine was rooted in more than just politics: The shot was released before medical trials were complete. But it’s now been approved in more than a dozen countries. A recent peer-review study in respected British medical journal the Lancet found that its efficacy was on par with the Pfizer-BioNTech and Moderna vaccines.

And with wealthier nations hoarding “Western” vaccines, a growing number of nations have turned to Russia, giving the Kremlin an image boost worldwide.

Even Brazil has gotten on board, despite the apparent pressure and the fact that its regulators still haven’t signed off. Last week, the government announced that it had reached a deal to buy 10 million doses of the Sputnik V vaccine.

The federal government announced its purchase of the Sputnik V vaccine one day after state governors had signed a deal with Russia to bring almost four times more doses to Brazil.

Brazilian President Jair Bolsonaro and his government have faced widespread criticism over slow negotiations to purchase vaccines from foreign companies. Over the past year, Bolsonaro has repeatedly dismissed the threat posed by covid-19, the disease caused by the coronavirus. He also tested positive twice for the coronavirus in July.

Meanwhile, the virus continues to spread rapidly in the country, straining an already overburdened health-care system. Only 2.3 percent of the population has received the two doses of the AstraZeneca or Sinovac vaccine.

Heloísa Traiano in Rio de Janeiro contributed to this report.