This means she has no chance of competing at the Rio 2016 Olympic Games.

The 30-year-old, a 1500 metres gold medallist at the London 2012 Olympic Games, was stripped of her title and banned because of abnormalities with blood levels found in her athlete biological passport (ABP) readings in 2013.

This followed a previous two-year doping ban awarded in 2004.

She had reached an agreement with the International Association of Athletics Federations (IAAF) last year and agreed to an eight-year suspension due to finish in 2021. 

Since then, however, she revealed that, in 2012, she had been told by the sons of former IAAF President Lamine Diack she could keep her Olympic gold medal if she paid them a bribe of €650,000 (£490,000/$700,000).

This entitled her to a reduced sentence, she claimed in an appeal lodged against the World Anti-Doping Agency (WADA) on Monday (July 4).

Under WADA rules, punishments can be reduced by up to 75 per cent for help in doping investigations.

CAS had already provisionally lifted the ban in order to provide the Turk with an opportunity to run a qualification time. 

She had made her return in Istanbul last Tuesday (June 28), running 4min 19.70sec for 1500m. 

This is more than 12 seconds slower than Olympic qualifying standard of 4:07:00.

But CAS dismissed her appeal and "as a consequence, the status of this athlete remains unchanged".

This came after another drugs cheat, Russian 800m runner Yuliya Stepanova, was granted permission to compete internationally by the IAAF after she provided evidence leading to the suspension last November of the All-Russia Athletic Federation for systemic doping.

The full verdict against Çakır is still to be distributed.