Russia is again working to hide key doping details from the World Anti-Doping Agency — which could impact its pending reinstatement.

Russian authorities prevented WADA officials from accessing doping data on Friday that it had previously agreed to hand over, according to the Associated Press. WADA said it “was unable to complete its mission” after Russia “unexpectedly demanded its equipment be certified under Russian law,” a demand WADA said was not raised until Friday.

The deadline to turnover the data is Dec. 31. That data would likely help WADA confirm specifics uncovered during investigations into the Russian doping scandal — something that alleged widespread, state-sponsored doping for its athletes during the 2014 Olympics in Sochi. Russian track athletes were banned from the 2016 Summer Olympics, and only athletes not involved in the doping scandal were allowed to compete in the 2018 Olympics in PyeongChang, South Korea, however had to do so as “Olympic Athletes from Russia.”

“Surprise, surprise — anyone shocked by this?” Travis Tygart, the CEO of the U.S. Anti-Doping Agency, told the Associated Press. “Let’s hope WADA leadership has finally learned the lesson and immediately declares them non-compliant. Anything else is simply another shiv in the back of clean athletes.”

WADA had voted to reinstate the Russia Anti-Doping Agency (RUSADA) in September after it had been declared non-compliant and suspended in November 2015. Without handing over that data — something WADA saw as a key reason to reinstate them — Russia’s reinstatement could be in jeopardy. Per the report, the WADA compliance review committee will meet in January, where it will receive a report from WADA team leader Toni Pascual on its failed mission in Russia.

Russian Sports Minister Pavel Kolobkov and WADA said it would return to the lab again, however no date or specifics was mentioned.

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