The Court of Arbitration for Sport on Friday upheld the International Association of Athletics Federation's ban on Russian track and field athletes at the upcoming 2016 Olympics in Rio de Janeiro, dealing a blow to 68 Russian athletes who had challenged the ban.

"The CAS has dismissed both the request for arbitration filed by the ROC and 68 Claimant Athletes, and the appeal filed by 67 of the same athletes against the IAAF decision to consider them ineligible for the Olympic Games in Rio," said the international body, in a release.

The IAAF had banned Russian track and field athletes from competing at the Olympics in November last year, after a report by the World Anti-Doping Agency indicted Russia of conducting state-sponsored doping programmes. They decided to continue the ban in a recent meeting in June, earlier this year.

Russia faces the prospect of all its athletes being banned from the upcoming event after a new report on Tuesday from WADA found fresh evidence of doping malpractices in the country. The International Olympic Committee is expected to take a final call in the next few days.