A spokesman for Russian President Vladimir Putin says accusations of widespread and systemic cheating by the country's track and field athletes in a report commissioned by the World Anti-Doping Agency are "groundless."
The report recommended that the IAAF suspend the All-Russia Athletics Federation from competing amid the allegations of cheating and cover-ups.
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However, Kremlin spokesman Dmitry Peskov insisted Tuesday that no evidence has been put forward so the accusations have no basis.
"The thing is that if accusations are being voiced, they should be supported by proof," Peskov said. "Until proof is presented, it is difficult to accept these accusations. They are quite groundless."
UK Athletics chief Ed Warner backed calls for Russia to be banned from the sport and considered their denial of the findings "insulting."
"I'm sure there are other options (than banning Russia), but it's the one I'd choose," he told Sky Sports.
"Russia needs to demonstrate it cares about clean sport, can deliver clean athletes and respects the integrity of athletic competition.
"If they had a modicum of shame they would withdraw themselves.
"I think it is insulting. There are athletes from all over world that have been cheated out of medals, hearing their national anthem on podium and maybe making finals.
"In many places, including Britain, losing lottery funding because they didn't meet the necessary requirements as a result of Russian cheats."