Russia’s return to international sport has been delayed following allegations that its head of anti-doping was involved in covering up drug test results at the 2014 Sochi Winter Olympics.

While the International Olympic Committee said on Thursday that athletes from Belarus should now be free to compete under their own flag and anthem, it admitted it still had “concern” over Russia.

Sources have confirmed that concern relates to recently reported claims linking the Russian anti-doping agency’s director general, Veronika Loginova, with the government-supported doping programme at the Sochi Games.

While not naming Loginova, the IOC’s president, Kirsty Coventry, said the allegations had caused “great concern” and had “led to the World Anti-Doping Agency [Wada] looking into a potential doping allegation”.

“It is of huge importance for me to do whatever we can to ensure that the field of play, whenever any athletes are coming back to competition, is the cleanest and fairest field of play that we can provide,” added Coventry.

The allegations, which were first published in the Insider in April, also claimed that Loginova’s partner was a member of the Russian security service, the FSB. Under Wada rules, there should be no government interference in a country’s anti-doping programme.

In a statement, Wada said it “noted with concern the contents of an article published by the Insider that made certain allegations related to the chief executive of Rusada and the anti-doping system in Russia.

“Wada is taking these allegations very seriously and immediately alerted its independent Intelligence and Investigations department accordingly,” it added.

In its statement, Wada also told the Guardian that since December 2025 it had been looking into “another serious allegation made by a known source against the same individual”.

“While Wada will not speculate on what the findings of the latest Russia-related enquiry might be, if the allegations made either by the source or The Insider article were verified, it would be a cause of significant concern for Wada, and further action would be initiated,” it said.

Last month Loginova dismissed the accusations as “fantasies” and told the New York Times she was working on educational programmes during the 2014 Games. “I had no potential involvement in the anti-doping laboratory’s operations, much less influence on the collection of doping samples and their subsequent testing,” she said.

Rusada has been approached by the Guardian for comment.

However, the IOC’s decision was greeted with frustration by Russia’s sports minister, Mikhail Degtyarev. “The Russian Olympic Committee has long since provided the IOC with a comprehensive set of documents demonstrating the elimination of all legal grounds for further banning the ROC,” he said. “Linking the decision to reinstate the ROC to any irrelevant matters is unacceptable. The restoration process has clearly been delayed, and we see no reason for it.”

Meanwhile World Athletics said it would not be welcoming Belarus or Russia back into the sporting fold until there was “tangible movement” over peace negotiations in Ukraine.

“We all hope this will be soon, but until that happens the Council continues to be united in standing behind the decision it made in March 2022 and revisited in 2023 and 2025,” it added.