The case of the seven Russian athletes banned for swapping urine samples has been sent to the Court of Arbitration for Sport (CAS) after a bitter dispute broke out over their fate.

The All-Russia Athletic Federation (ARAF) incurred the wrath of the IAAF, the world governing body, last month by backdating a blanket two-year suspension to the date of the original offence, thus freeing the athletes to compete at next year's World Championships. That was viewed as a cynical manipulation of events by the IAAF, which has appealed to CAS.

Lamine Diack, the IAAF president, said: “It is unacceptable that these athletes, who have committed serious and deliberate breaches of our anti-doping rules, would receive an effective ban of nine to ten months. I consider the circumstances warrants the IAAF to seek an extended ban above the minimum two-year period.”

The athletes include Tatyana Tomashova, the two-times world 1,500 metres champion, and Yelena Soboleva, the world indoor 1,500 metres champion. Lisa Dobriskey, Britain's Commonwealth champion at the distance, said: “They are trying to cheat the system and they have cast a shadow over the whole event.”

The athletes were provisionally suspended by the IAAF in July on the eve of the Olympic Games. ARAF accepted the athletes' guilt, but claimed that the bans should start from the date of the first positive sample, which was in April 2007.

The IAAF said that the date of any sanction cannot start before the day the athlete was provisionally suspended from competition. Yelena Isinbayeva, the world-champion pole vaulter from Russia, challenged those who claim that there is a doping problem in the country. “I think it is because we are so strong that they want to destroy us,” she told The Times. “I think it is a political thing.”