Jamaican sprinter Asafa Powell, the former 100m world record holder, has appealed to the Court of Arbitration for Sport (CAS) against his 18-month doping ban. Powell and training partner Sherone Simpson tested positive for banned stimulant oxilofrine after the 100m finals at the Jamaican nationals on June 21, 2013. Powell, who blamed his positive result on a nutritional supplement, was banned until December 28, 2014 by the Jamaica Anti-Doping Commission Disciplinary Panel. The 2008 Olympic champion in the 4x100m relay has requested that CAS cut the suspension to three months, the international body's secretary general Matthieu Reeb told AFP on Monday. The date of the hearing has not yet been fixed. Simpson is also appealing her 18-month suspension. Powell, who held the 100m world record between June 2005 and May 2008, believes the punishment is too severe for the level and nature of the offence. He blamed Canadian physical therapist Chris Xuereb for the positive test, saying he provided the nutritional supplement, Epiphany D1, that resulted in the failed test. Jamaican athletics great Veronica Campbell-Brown was cleared to compete in February after CAS confirmed she had been found not guilty of a doping violation. The 31-year-old -- only the second woman athlete to win successive 200m Olympic titles when she won in 2004 and 2008 -- missed last year's outdoor world championships after she tested positive for a banned diuretic, hydrochlorothiazide. Source: AFP