The chief executive of the track and field governing body in running powerhouse Kenya has temporarily stepped aside after two athletes alleged in an interview with The Associated Press that he asked them for a bribe to reduce their bans for doping.

Isaac Mwangi said in a letter to the Athletics Kenya president that the allegations from 400 metre runner Joy Sakari and Francisca Koki Manunga, a 400m hurdler, were "unsubstantiated" and "have caused me a lot of mental anguish."

He asked for 21 days leave while the allegations are investigated.