KINGSTON, Aug 5 (Reuters) - Jamaican 4x100m relay team member Julien Dunkley said he had been told that he had tested positive for a banned substance and would not be competing for the Caribbean country in the Beijing Olympics.

Dunkley, 32, was told he tested positive for an undisclosed substance at Jamaicas national championships in late June. Media reports have named the substance as the anabolic steroid boldenone.

Dunkley told local radio from his home base in North Carolina that the Jamaica Amateur Athletic Association had told him of the positive test of an A sample after he called them.

I will request that the B sample gets tested as I have never taken drugs in my life and I dont know about this drug, Dunkley said. (Reporting by Horace Helps, Editing by Michael Christie)