The governing body of world athletics on Tuesday maintained Russia's ban from track and field over mass state-backed doping, citing two conditions before the powerhouse can return to international competition.
Rune Andersen, head of the IAAF's taskforce on Russia, said Russian authorities had to grant access to data from testing of samples at a Moscow laboratory from 2011 to 2015 and also pay the IAAF's costs.
Access to the samples would hand the Athletics Integrity Unit, the independent body that manages all doping and non-doping integrity-related matters in athletics, the opportunity to determine whether any suspicious findings should be investigated.
"I hope they'll deliver the data by the end of this year," Andersen said of the samples taken and stored in the Moscow laboratory. "But I cannot go any further than that.
"We've received no assurances it will be delivered to us directly," the Norwegian said of the data.
"Assurances have been given to Wada (World Anti-Doping Agency) and Wada have set a deadline of December 31 to receive the data. We'll have to rely on receiving the data from WADA before handing it to the AIU."
The IAAF's decision means Russia will not, for the moment, be able to compete under its own flag at the European Indoor Championships in Glasgow in February 2019, with the IAAF Council not scheduled to meet again until March.