US champion Bryan Bronson, the world's leading 400 metres hurdler, has been suspended after a positive dope test in Rome on July 14th last year. Bronson won bronze at the 1997 World Championships in Athens.

A laboratory analysis of Bronson's urine sample in Rome was found to have "abnormal steroid concentrations".

Speaking from the International Amateur Athletic Federation (IAAF) headquarters in Monaco yesterday spokesman Giorgio Reineri said Bronson had been suspended on March 19th this year.

Explaining the eight-month delay between the positive test finding and the athlete's suspension, Reineri said: "This is a very delicate case. After he tested positive, Bronson was asked to explain himself. He sent to us an explanation from his lawyer and a doctor, saying that he had some medical problem. We took the decision not to suspend him immediately, but to await a full medical report.

"We took into consideration Bronson's explanation, and so we allowed him to continue to compete through last summer. We have followed the rules as carefully as possible."

Bronson was allowed to race all last season. He reached the Grand Prix final in Moscow last September poised to collect a possible $400,000 in prizemoney and bonuses as part of the IAAF's one million dollar jackpot. But after Bronson clipped the final flight of hurdles in his race, he missed out on the Golden League jackpot and ended up winning just $57,000. The IAAF said yesterday that his prizemoney had been withheld.

"We waited for nearly six months to receive his medical report," Reinari said. "The medical report was never sent, and it was impossible for us to reach Bronson, and so we have suspended him."

Bronson is the third top athlete to be suspended for drug use in the past month. Vita Pavlysh, the Ukrainian who won the women's shot put at last month's world indoor championships in Japan, was stripped of her title following a positive test. On Wednesday, European 200 metres champion Doug Walker was suspended pending a hearing.