Story highlights IOC review panel recommends Russian athletes and support staff cleared on appeal should not participate in Games

(CNN) In a fresh twist to the doping saga that threatens to overshadow the Winter Olympics, the International Olympic Committee (IOC) has refused a request for 15 Russian athletes and coaches "cleared of doping" to attend the PyeongChang Games.

The 13 athletes and two coaches were among 28 Russians whose lifetime bans for doping were overturned by the Swiss-based Court of Arbitration for Sport (CAS) Thursday.

CAS ruled there was insufficient evidence to show they had broken doping rules during the 2014 Sochi Winter Olympics.

But the IOC said Monday its invitation review panel examined applications on behalf of the 15 individuals and had lingering suspicions about potential anti-doping violations.

The row puts the IOC, which has always claimed to have the final say on which athletes compete in the Games, at loggerheads with sports law's highest court just days before the Olympics begin in South Korea on February 9.