International Olympic Committee (IOC) chief Thomas Bach said the Court of Arbitration for Sport's decision to uphold the appeals of 28 Russians against Olympic life bans was unexpected.
A decision by sport's top court to lift life bans for doping of 28 Russian athletes was "extremely disappointing and surprising," International Olympic Committee (IOC) chief Thomas Bach said on Sunday.
He said that the ruling came as a complete surprise to the IOC.
"We would never have expected this," Bach told a press conference in Pyeongchang just five days ahead of the opening of the Winter Olympic Games.
The IOC's disciplinary commission banned 43 Russian athletes for life and disqualified all Russians from competing at the Pyeongchang Games over a state-sponsored doping conspiracy.
It later ruled that 169 athletes who had proved they were clean would be allowed to compete.
The Court of Arbitration for Sport on Thursday upheld the appeals of the 28 Russians against the Olympic life bans, ruling there was "insufficient" evidence that the athletes had benefited from the doping system at the 2014 Winter Games, hosted by Russia.
Bach said that Olympic officials had asked CAS for an explanation for their ruling and had been told no full accounting would be released until the end of February.
The Games in South Korea end on February 25.
He said the IOC knew only what had been released by CAS in a press statement and this was "extremely unsatisfactory given the gravity of the cases."
"We feel that this decision shows the urgent need for reforms in the internal structure of CAS," he added.
On Saturday, the IOC said that 13 of the 28 athletes cleared by CAS would be considered by a special IOC panel for a possible invitation to take part in the Pyeongchang Olympics.
But Bach said: "The absence of sanctions by CAS does not mean that you are entitled to receive an invitation from the IOC because receiving this invitation is a privilege of clean Russian athletes."