FOUR Olympic athletes face bans if the International Olympic Committee (IOC) decides to retest their urine samples from the Atlanta Olympics.

IOC medical director, Patrick Schamash, said yesterday there had been four unannounced "positive results" from Atlanta for anabolic steroids.

But he said the IOC had not been satisfied about the reliability of the testing procedures conducted on the high resolution mass spectrometer, used for the first time at an Olympics in Atlanta.

"They were positive results," he said. "Not positive cases. We are not 100 per cent sure that the tests were positive.

"We don't want to spoil the athletes' lives if we are not 100 per-cent sure. We want to be very clear."

Schamash said a decision on whether or not to retest the athletes' samples would be made at a medical sub-commission meeting within the next two weeks.

He said he did not know the identity of the athletes or which sports were involved.

We will decide whether to retest," he said. "There's no wish to hide something."

Bulgarian women's triple-jumper, Iva Prandzheva, and Russian women's high hurdler, Nalalya Shekodanova, tested positive for steroids in Atlanta on the standard mass spectrometer and were banned for four years.

Sprinter Ben Johnson, banned for life in 1993 after a second positive drug test, said on Tuesday that he wants to be reinstatement so he can run again and prove he "still is the best sprinter" in the world.

"Well I just want to re-write the books, the history books, and prove that I am still the best sprinter that ever ran track and field. I want to go back on the international circuit," said Johnson.

Johnson, who will be 35 in December, was suspended from competition for life by the International Amateur Athletic Federation in 1993 after testing positive for an excessive amount of the male hormone testosterone at a Grand Prix track meet in Montreal on January 17th, 1993. At the lime Johnson denied he had used any banned drug but said he would not appeal the suspension because a legal challenge would be too expensive.

Johnson's manager, Morris Chrobotek, told CBC Newsworld that he and Johnson had spoken recently with track and field officials in Ottawa about a possible reinstatement.

Chrobotck did not elaborate on what grounds a request for reinstatement would be based although he suggested there was a flaw in the testing procedure. Johnson had passed a drug test at a competition two days prior to the Montreal meet and passed another lest four days afterwards.,

Johnson's first drug suspension came at the 1988 Seoul Olympics where he was stripped of his 100-metre gold medal and world record clocking of 9.79 seconds after he tested positive for the banned steroid, stanozolol.

Earlier on Tuesday at a press conference in Toronto, Canada's Donovan Bailey and Michael Johnson of the US announced they would meet in a 150-metre match race on May 31st, with the winner to receive $ 1.5-million and claim to the title of the world's fastest man.

Bailey set the world 100-metre record in winning the Olympic gold medal in Atlanta. Johnson won gold in the 200 and 400 metre events at the Atlanta Games sparking immediate debate over which sprinter should be dubbed the world's fastest human. The city and venue for the showdown will be announced at a later date.

Athletes setting world records at next year's Athens world championships could earn a $ 100,000 bonus, IAAF sources said yesterday.