UK Athletics said today that clenbuterol, a stimulant used in asthma treatment, was found in his sample after a test in South Africa in January and he was provisionally suspended under IAAF (International Association of Athletics Federations) rules.

The Londoner, who competes for Woodford Green, faces a two-year suspension and a lifetime ban from the Olympics under the rules of the British Olympic Association (BOA).

Priestley won the 60 metres hurdles at the British Indoor Championships in Sheffield last month and was considered a rising star in the sport.

He was included on the Olympic development programme, announced last October, and last summer won a bronze medal at the European Under-23 Championships.

Priestley is coached by Lloyd Cowan, who also trains Olympic and world 400m champion Christie Ohuruogu, at the Lee Valley High Performance Centre.

Priestley is the first British athlete to test positive for a banned drug since Dwain Chambers in August 2003.

"I am hugely disappointed there has been a failed test," UK Athletics chief executive Niels de Vos said in a statement.

"UKA continues to give 100 percent support to the work of UK Anti-Doping and we maintain our full commitment to drug-free sport."

Priestley, who won the 60 metres hurdles at the UK Indoor Championships last month, could face a two-year ban unless he proves he had a valid reason for having the drug in his system.

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