The Court of Arbitration for Sport on Thursday dismissed a Russian appeal against a ban imposed by athletics governing body over state-run doping that rules the country out of the Rio Olympics track and field.

CAS said its panel unanimously "confirmed the validity" of the International Association of Athletics Federations decision to ban Russia from Rio because the country is suspended from the world body.

The Russian Olympic Committee (ROC) "is not entitled to nominate Russian track and field athletes to compete at the Rio 2016 Olympic Games", the ruling said.

The International Olympic Committee has said the CAS ruling will help shape its decision whether to ban Russia entirely from the Rio over an investigation which accused Russia of rampant state-backed doping at the 2014 Sochi Winter Olympics and other major events.

The Russian Olympic Committee and 67 Russian athletes had sought to overturn the IAAF ban after a World Anti-Doping Agency investigation documented widespread doping in the country's track and field programme.

The IAAF said the Russian athletics programme had been tainted to the point where even negative drug tests could not be trusted.

The ROC and 68 athletes had challenged the IAAF's right to punish those who had never tested positive for doping. US-based long jumper Darya Klishina has since been cleared to compete in Rio however.

The IAAF has said individuals who could definitely prove they were not tainted by the country's corrupt system could be eligible for Rio.

CAS also said any Russian athlete who met the IAAF's elibililty criteria could be cleared for Olympic competition.

"The ROC is entitled to enter as representatives of the Russian Federation in the Rio 2016 Olympic Games the Russian track and field athletes who fulfil the criteria and are eligible to compete under IAAF," the judgement said.